Stalling / won't idle - electrical problem?

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Jerry
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Posts: 62
Joined: Tue Dec 14, 2004 3:13 pm
Location: Bakersfield, CA USA

Post by Jerry »

Hi gang,

Just drove my '84 on a short (less than 2 mile) errand this afternoon. Upon setting out for another destination, all of a sudden the car won't idle, and the charge and brake warning lights are on.

I get it home and park in the driveway. (Driving home, every time the engine dropped to about 1200 RPM, the engine would no longer idle and would die. Turning the key would get it started again - that really would have been embarasssing to call for a tow with my wife in the car!)

With the engine off, I check my charge on the battery using a voltmeter across the battery terminals - 12.3 volts, seems OK to me.

Looking in the fuse box under the hood, I noticed the engine one was blown. So, I replace with another 15 amp fuse, restart the engine, revving it up a little bit. When the engine dies I shut off the ignition and check the fuse - the new one has blown as well.

Anybody have a prelimary diagnosis? Voltage regulator? Alternator?

Thanks,

Jerry
Jerry
Bakersfield, CA
Owner of a rusty '84 Terc SR5 4WD
251,000+ miles, original engine, second transmission.

Transmission soon to GRENADE!
Jerry
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Posts: 62
Joined: Tue Dec 14, 2004 3:13 pm
Location: Bakersfield, CA USA

Post by Jerry »

C'mon, there's got to be someone out there that can help... Please?

Thank you,

Jerry
Jerry
Bakersfield, CA
Owner of a rusty '84 Terc SR5 4WD
251,000+ miles, original engine, second transmission.

Transmission soon to GRENADE!
GTSSportCoupe
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Posts: 1626
Joined: Thu Apr 01, 2004 9:14 am
Location: Victoria BC, Canada

Post by GTSSportCoupe »

I wish I had a quick answer for you...but I don't :unsure: . What I would suggest, is look in the Factory Repair Manual (you can download from our main site) at the electrical diagrams. Look to see what electrical components are connected via the fuse that has blown on your car. Then test each of these components as described in the Repair Manual. Replace the part that tests out as faulty. Thats how I'd approach the problem anyhow... ;)

I've never had this prob, otherwise I'd suggest some specific things...
Current:
91 LJ78 Landcruiser EX5
95 A32 Maxima SE
Former:
87 AW11 MR2 Smallport 4AGZE
93 Taurus SHO ATX
86 AL25 SR5 6spd 4wd
90 AE92 GTS
82 KP61 SR5
85 MX73
87 AE86 GTS 4AGZE
85 AE86 GTS
83 AL21
takza
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Posts: 4414
Joined: Fri Apr 02, 2004 4:28 am
Location: Tibetan plateau

Post by takza »

The charge & brake lights being on are a sign of alternator problems.
Give a boy a gun-give a biatch a cell phone-and pretty soon you almost got yourself a police state.

Orwell said: War is peace! Freedom is slavery. Ignorance is strength...

Image
Jerry
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Posts: 62
Joined: Tue Dec 14, 2004 3:13 pm
Location: Bakersfield, CA USA

Post by Jerry »

Thanks, Takza. I really do appreciate it.

Hopefully this will greatly cut down my troubleshooting time. I really need the car by Wednesday. :)

Jerry
Jerry
Bakersfield, CA
Owner of a rusty '84 Terc SR5 4WD
251,000+ miles, original engine, second transmission.

Transmission soon to GRENADE!
Jerry
Advanced Member
Posts: 62
Joined: Tue Dec 14, 2004 3:13 pm
Location: Bakersfield, CA USA

Post by Jerry »

Well,

The good news is the alternator replacement went smoothly.

The bad news is that the alt and brake warning lights are still on. :(

Anybody know a good source for an external voltage regulator for my '84?

TIA,

Jerry
Jerry
Bakersfield, CA
Owner of a rusty '84 Terc SR5 4WD
251,000+ miles, original engine, second transmission.

Transmission soon to GRENADE!
takza
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Posts: 4414
Joined: Fri Apr 02, 2004 4:28 am
Location: Tibetan plateau

Post by takza »

I replaced the alt/reg on an '83...and what I read said to replace BOTH at the same time....tho I was given a faulty NEW reg where I spent a week assuming it was good and tested the crap out of everything else. Think I got mine at AdvanceAP. :lol:
Give a boy a gun-give a biatch a cell phone-and pretty soon you almost got yourself a police state.

Orwell said: War is peace! Freedom is slavery. Ignorance is strength...

Image
Chris
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Posts: 110
Joined: Sun Nov 21, 2004 12:16 am
Location: Northern Utah

Post by Chris »

After the alternator replacement...is the fuse still blowing? Does the engine idle any better?
Teddy1
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Posts: 75
Joined: Mon Jan 12, 2015 10:26 am

Post by Teddy1 »

Jerry:

Posted earlier: " The charge & brake lights being on are a sign of alternator problems. "

Actually, this isn't true. The alternator ISN'T suspect here, because you already indicated that you were blowing fuses, and, the car WILL restart with the ignition key, which indicates that the alternator was routinely charging the battery enough to restart the car.

Basic troubleshooting on your car's systems should look something like this (basically in this order):

a) obtain a load tester, or borrow one from your local auto parts store. Remove the cables from the battery under your hood, and then clamp the load tester to your battery. Throw the switch (if it is an analog unit) for 10 seconds, and then note where the needle says your battery is... if you are not producing at least 600 CCA (cranking amperage is a surge + amp hour rating) then your battery is suspect. If the battery has plate damage/sulfating/electrolytic issues, then your charging system is going to be hosed, as it will be attempting to charge a battery than cannot accept a charge. A voltmeter is mostly useless on a battery that is not in use... other than to simply indicate if the battery is up to the correct 13.2-13.5 resting voltage. A battery that shows 12.5 volts on a voltmeter MIGHT dip to 3 volts under starting load, due to failed cells/tired battery/shorts. A load tester, on the other hand, puts an actual electro-mechanical LOAD in front of the battery, which allows you to monitor amperage and voltage in a simulated "starting" environment. I do not suspect your battery in this equation...

HOWEVER. Good troubleshooting will always start with load testing of the battery.
Of interest here would be the clamps on the battery (clean?) the cable running to the starter (clean and not melted?) and the wires on the back of the alternator.

B) verify that you see at LEAST 13.2-13.5 volts at the battery terminals when the car is idling... if the car will not idle, have an assistant keep the car running by pressing on the gas pedal, and use a voltmeter at the battery terminals to check alternator output. Here we should be able to rule out (or suspect) alternator or regulator and/or fusible links.

c) verify the quality/integrity of your grounds... ESPECIALLY the one that go to the side of the engine block, and the one from the battery to the body and then to the remainder of the electricaly system. Fuses popping and burned fusible links are strong indicators of failed grounds. Look for green corrosion on the copper, check that no wires have frayed/broken. Feel free to use a wire brush and some carb cleaner on those ring connectors... after you have scrubbed them shiny again, clean them with brake cleaner (or electrical contact cleaner), then spray them with silicone, then rebolt them/clamp them to wherever they are supposed to go.

d) if an aftermarket radio/stereo/head unit/ham radio/cb has been installed, check the install... any shorts? Shoddy harness work/shorts behind the dash can cause grief.

e) often, if there IS a problem behind the dash, the cigarette lighter won't work! Simple test! Push in the lighter.

f) while you are in there, honk the horn. Is it loud and clear? If so, your low tension to dash to engine bay electricals are probably pretty squared away. Check the headlights, too.

g) check the OTHER fuses under the dash... not just the ones under the hood!

h) believe it or not, corrosion in bulb sockets and the like can wreak havoc on electrical system troubleshooting... turn on your lights, and walk around the car... do all of the lamps light up? turn signals? hazards? flashers? How about the windshield wipers?

i) feel free to SAVE YOURSELF PAIN, and remove many of the fuses under the dash, anyways... the cigarette lighter fuse, the wipers, the defroster, the blower motor, the radio, interior lights, etc.

Let me know if I can help you from here...

- Teddy
Teddy1
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Posts: 75
Joined: Mon Jan 12, 2015 10:26 am

Post by Teddy1 »

My first impression SOLELY from what you have told me is...

Vaccum leak. Maybe at the distributor? Or, one of the hoses under the airbox?
Teddy1
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Posts: 75
Joined: Mon Jan 12, 2015 10:26 am

Post by Teddy1 »

Wait. You said:

"Just drove my '84 on a short (less than 2 mile) errand this afternoon. Upon setting out for another destination, all of a sudden the car won't idle, and the charge and brake warning lights are on. "

Do you mean, they are on ALL of the time when the car is running, or, only when the car is ABOUT to die (like at low rpms)?

Because this will fairly effectively rule out either vaccum leak or electrical issue...
Jerry
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Joined: Tue Dec 14, 2004 3:13 pm
Location: Bakersfield, CA USA

Post by Jerry »

Thanks to all who've chimed in, especially Teddy. I really appreciate the time to go through that.

I just finished replacing the regulator (so, for those of you keeping score - new alternator last night, new regulator [external, I have the 50 amp setup]) this evening.

In the fuse box under the hood, the 15 amp fuse labeled "Engine" keeps blowing. The charging and brake warning lights are both on. The other fuses on the driver's side kick panel are all OK.

Even with the engine revving at around 2000RPM (fast cold idle), I'm only getting 12.2 - 12.3 volts on the multimeter. So, doesn't look like the alternator is "getting to" the battery. Bad ground, fusible link?

The battery cranks the car over just fine. While I haven't checked the chassis ground specifically, I did top off the watter in the battery, and clean and tighten the terminals.

If I kick the car off fast idle, and let it get down to about 1000 RPM, the car will start running rough and immediately die. Interestingly enough, it will immediately restart - go figure.

I do have a question regarding alternator wiring - there is the connector that clips in, then one skinny wire going to the post on the right. (As you're facing it from the front of the car, installed in car). On the left hand post on the alternator,, is there anything supposed to be connected there aside from the condenser? I know that's kind of a stupid question, but hey I was tired last night when I put the new alternator in... And looked around for 10 minutes for something to connect to that post, but didn't find anything.

I tested the fusible links in the underhood fusebox for continuity... They seem OK. Is there another fusible link elsewhere that I might be missing?

Really, thank you again guys. I really do appreciate your input.

Jerry
Jerry
Bakersfield, CA
Owner of a rusty '84 Terc SR5 4WD
251,000+ miles, original engine, second transmission.

Transmission soon to GRENADE!
Teddy1
Advanced Member
Posts: 75
Joined: Mon Jan 12, 2015 10:26 am

Post by Teddy1 »

Jerry:

Dude, I have your car. EXACTLY your car. A 1984 Toyota Tercel 4WD Wagon SR5 in the silver color.

I will go out in the morning and take a photo of the back of my alternator for you.

- Teddy
takza
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Location: Tibetan plateau

Post by takza »

Try a google NG search on "toyota charge brake lights"etc........very common with '80s Toyotas? Lot of different ideas......

But wait...I already did that....


-----------


My daughter has an 86 Toyota Corolla with about 165,000 miles on it. Still runs well. I had to change the ball joint the other day and when she drove home about an hour later she made a turn and ****the ALTERNATOR LIGHT came on + the BRAKE LIGHT.****

Belts are TIGHT and were REPLACE about 1 year ago. Battery teminals are clean.

I told her to check the brake fluid level. She added a little but the light
stayed on.

Next day, BOTH lights were off but came on after a fairly short drive. Then
they went off. Now they are back on.

How can I tell if it is the ALTERNATOR or REGULATOR. BOTH
parts are about $80 - 90. I found one place with the regulator for $50. All are special orders.

I told my daughter and her boyfriend to put a VOM on the battery terminals and
rev the engine to about 2,000 rpm. They said the VOM did not move on DC volts.

Sound like the alternator.

However since the lights come on and go off, it sounds to me like a LOOSE or
CORRODED connection. Time to start JIGGLING things. I have to travel an hour
away to do so and would like more advice.

TIA

John wrote:

> You need to have them measure the voltage across the battery terminals. With
> the car off, it should be around 11.75 to 12 volts. Start the car and it
> should read around 13 volts. Then turn on the headlights and the voltage
> should only dip slightly. If the voltages are below 12, then check the
> brushes.



If it dips below about 13.8, your going to be in trouble, older cars
with little loads, you could get by with 13.5, this is of course, peak
voltage, this shows up after the battery has replenished, if under heavy
charge, ie a dead battery, voltage will be low, current high, as the
current drops, voltage will climb, normally, this voltage will level off
at 14.5-14.8, though, 15.1 is OK, its tough on batteries, this will make
them hot and gas more, both sortening overall life.

----------

Hello:

I own a 86 camry. ***The charge light comes on along with the brake light.***
First it started flashing when i turn on the car and now it comes on while
driving. It goes off after a while. If this problem is with the
alternator, how come the brake lights also comes on. One of the mechanics
feels it is the alternator and is charging me about $350, and hence i want
to get your opinion also.

I have a new battery and no problem in starting.

I appreciate your input

Aswin


I had an '86 Corolla that had the same problem, the brake and charge light were
on when I drove.

The first mechanic replaced the right rear brake cylinder. That did nothing
for either the brake or charge warning light problem.

I then took it to a Toyota dealer. They said it was either the brushes (next
to the alternator?) or the alternator. They suggested getting a new
alternator, which I did, and the warning lights stopped flashing.

So I don't know if it was the brushes or the alternator, but the alternator, in
general, was the culprit, in my case anyway.


***As a test of the bulb, the brake light is supposed to come on with
the key on, engine off, even if the handbrake is not applied. It is
turned off by output from the yellow wire at the alternator, as is the
charge light. The yellow wire is energized by the built-in IC regulator
in the alternator. It is possible for the regulator to fail to output
voltage to the yellow wire even though the alternator is actually
charging.***


"Dammit Jim! I'm an Automotive Service
Technician, not a mechanic!!"
Steve S.


Dave, the field circuit (rotor, brushes and regulator) is actually the
ground path for the light on many models, when the field circuit fails
and becomes open, as it will do with worn brushes, the path to ground
for the light bulb is gone, but when you turn the key on and the car
isn't running, you'll see the charge lamp isn't lit for the check
function. Many makers have alleviated this by putting in a 40 ohm
resistor to provide an alternate path to ground so you will still get
the light.



***Rick Jones***

***Toyota Master Diagnostic Technician/ASE Master/L-1***


To check this your self:
You can check to see if it is the alternator if you have access to a
voltmeter. Place the voltmeter black lead (may be labeled - <minus> or
negative) on the negative (black) post of the battery or on any
exposed metal part of the car (engine) and the red lead (may be labled
+ <plus> or positive) on the positive battery post or on the output of
the alternator (large red wire or the largest wire of the 3-4 wires on
the alternator). With the engine off you should read 11 - 12 volts DC.
Start the engine and the reading should now read 13.5 to 14.9 volts DC
(voltage readings are approximations. A variation of a few tenths of a
volt are fine) If the charge light comes on and the voltage doesn't
drop back down to 11-12 volts or rise quite a bit higher than 14+
volts then the alternator is fine. If the reading drops then you most
likely have worn alternator brushes in the alternator. If it goes
higher then you have a voltage regulator problem.

If you do not have a voltage meter available then you can do the same
test at night (or some place dark. DO NOT do this in the garage with
the door closed) and watch the headlights. They should be brighter
with the engine running than with the engine off. If the get dim when
the charge light comes on then it is the brushes in the alternator.

OR - most auto parts stores have a battery tester that checks the
condition of the charging system. Saves them from replacing batteries
under warranty when the charging system is at fault.

Most shops will not replace just the brushes. Brushes are under $10 at
the dealer or some parts stores. Alternators are a whole lot more.

This got long winded....hope it helps.


---------------------

I have a '86 Toyota pickup and both the brake light and charge light
have been on together for about 3 years. Any ideas what causes that? I
have no charging problems, and the charging system analyzer I tested it
with indicates no problems whatsover. I have heard of another having
the same problem, but no solution.



I thought I was the only one that has had that problem, I also have an
86 toy and periodically those two lights come on. It has happened several
times as a result of loose or corroded battery connectors, twice as a result
of a dead alternator and other times it has been a short in one of the many
plugs coming from all the smog stuff on the passanger side inner fender. I
don't remember specifically which one it was but I disconnected them all and
cleaned out the contacts which had become filled with dried mud as a result
of too much offroading. Don't be afraid to disconnect them as they are all
unique and will only plug back into the proper sockets.
-Rich


Sounds like a bad voltage regulator which is built in on your rig. There
is a transistor that turns the light off when it sees the alt charging,
since the alt is charging, we can suspect the transistor in the
regulator.



***Rick Jones***

***Toyota Master Diagnostic Technician/ASE Master/L-1***


had the same problem, traced it down to the plug in connection at the
alternator.

One of your diodes in the altenator is bad. The alt will still put out
fine but it causes these two lights to come on. You have to buy the
whole alt. You cannot buy just diodes anymore.

-------------


Can anyone help me?

This morning my wife came in and told me that the brake warning light and
charge warning light were both lit on our '87 Tercel. It is strange that
they would both suddenly be on at the same time.

To turn off the brake warning light, I checked the brake fluid level (ok),
and made sure the parking brake was off. The center brake light was loose
and flickered off and on so I tightened the screw that held it in place and
it seems to be ok now but the brake warning light is still on. I've
checked every fuse on the car inside and out. Still on.

To address the charge warning light, I ran a volt meter across the battery
with the car off and it reads 12.8volts (ok). I started the car and with
the car running (and the charge light on) the volt meter across the battery
terminals reads 11.5 volts. I've cleaned the battery terminals and checked
all the fuses. Charge warning light is still on.

Maybe it's simply time to replace the alternator but the fact that the
brake light is on and the charge light is on makes me wonder if it is
something more weird. Anyway, if anyone has experienced this, I would
greatly appreciate a reply. It's probably the alternator but I was really
hoping it would be something simple.

Thanks!

Chris


get ready to buy an alternator. Same thing happened on my '92 Corolla. Wierd
how they turn on both lights, but that's the symptom. I've seen it here lots of
other times. I was the same - everyone comes on asking "what is this???"
Everytime I've looked, it's always turned out to be the alternator going bad.


I have a similar problem.

The facts:
84 tercel 4wd wagon
160K miles.
Automatic.

Sometimes while driving the charge, break, and temperature idiot lights
come on. Once the lights come on, everytime I take my foot off the gas
(for instance at a stop light/sign or I just want to slow down)
the car stalls. If I just turn the ****ignition key to start*****, the car starts,
but the idiots lights remain on and I will stall the next time I release
the gas.

Recently, I discovered I can fix the problem by ***turning the key back one
position to accessory and then back to start.**** This procedure will cause
the idiot lights to turn off and the car will allow the car to idle when
I don't give it gas. However, the idiot lights will come on in a few
minutes anyway.

Other tidbits of info.

The ignition key can be removed at any time and at any position. It can
even be removed while the car is on.

Do you think I need to replace the alternator and/or ignition switch.
I talked to a mechanic and he said he could fix it, but it might cost me
a lot of money since his labor rate is $50/hour and this is an
obscure problem.


John,

FYI to you and any who read this thread/newsgroup. I replaced my
alternator and my 87 Tercel runs fine now. Thanks to all that
responded.

It sounds like your problem is more obscure than mine. I'm not a
mechanic but I pretend to be one whenever there is a threat of money
leaving my wallet. See if you can buy/borrow a volt meter and measure
the voltage across your battery while the car is idling and when someone
revs it - you should get about 13.5 volts if your charging system is
working properly. If you get less than 13.5 volts when idling but get
13.5 volts when reving, check your idle speed - is it too low? Is the
belt too loose and slipping?

If I were you, I would inspect the ignition switch and the wires leading
to it for damage/shorts - this could cause the mysterious idiot lights
going off when in ACC. mode. This could also be the reason for
"intermittant" problems with your idiot lights instead of them being on
all the time.

I hope this is of some help to you. Oh, by the way, if you want your
alternator checked for free, call a few parts shops and ask if they do
free inspections. I took mine to NAPA and they tested it for free - Pep
Boys does this too. You have to pull it out of the car though, they
won't do it for free if it is still in the car.

Good luck!

Chris

-----------


I have an '83 Toyota 4x4. When driving down the road sometimes the brake
indicator light and the battery charging light both come on at the same
time. Sometimes they even stay on together when I start the truck. If I
pull out the brake handle and push it back in hard the lights go off,
but not all the time. I thought the brake switch was bad, so I switched
it with another one. Same problem. Even changed out the whole instrument
panel assembly, but still the same. Alternator is good. It's been
checked out already. Why would alternator light and brake light be
coming on together? When pushing the brake switch manually, only brake
light comes on like it is supposed to. The problem is intermittent. Does
anyone know what the problem is? I'm scratching my head now.
Mike

Mike,

If you release the handbrake, with the key off, then turn the key to the
on position you'll notice that the brake light comes on even though the
brake is released. This is mainly for those idiots with automatics that
never use the handbrake, so they can tell that the bulb isn't burnt out
in the brake warning light. *******Under this circumstance, it's turned off by an output from the voltage regulator or charge light relay--not
charging output, but a separate wire, usually yellow, that's only there
to turn off the brake and charge lights.*******

If you are absolutely certain the alternator is ok, Your problem could
be in the ****voltage regulator or the charge light relay, or just a poor
contact at the fuse labelled "charge".***** If it's not the fuse,-try a
regulator first, and be sure to get the right one-some models had IC
regulators and others had Tirril (old-fashioned contact type). I think
83 4x4s, especially sold outside CA, had the IC type. The IC type are
flatter than the tirrill type.

If this doesn't help, try the charge light relay--small gray plastic box
up under the dash, I think on the driver side--should be marked as a
charge light relay.

"Dammit Jim! I'm an Automotive Service
Technician, not a mechanic!!"


-------------



Hello Lori,

Many years ago I had that problem on my '84 Toyota Van. A dealer charged me
hundreds of dollars to replace the alternator, but the problem returned a
few months later. I bought a Toyota service manual and decided to learn how
to fix my Toyota myself.

********I discovered the problem was caused by faulty
connections to the alternator. Besides the main power output terminal, there
is a plug on the back of the alternator with three smaller wires. On my
Toyota, these wires were not making a good connection and had begun to burn.
I cleaned the connector and repaired the wires by reterminating and
soldering them to their terminals. I also used heat shrink tubing to
reinsulate and protect the repaired connectors. After repairing all the
wiring, my alternator worked perfectly for years.********

On another occasion when the alternator failed, I followed the instructions
in the Toyota manual to test it and found the internal voltage regulator to
be at fault. It cost only a fraction of the price of a whole alternator and
was easy to replace by following the step-by-step instructions in the Toyota
manual. I have also taken the alternator completely apart for a thorough
cleaning, again following the easy Toyota instructions. Since a complete
alternator assembly can be expensive, it's worth trying to repair it first
before replacing.


-----------


Can anyone tell me why the brake and bat light come on, and the alternator
stops charging, all at the same time?

First time it happened (at startup), I wiggled the wires to the alternator
(after about 1/2 hour running) and it fixed, the next time it happened (also
at startup), it went away after a few minutes.

I can understand the charge light coming on, but the brake light as well??

This is a '90 4Runner, 3 L V6, 190K miles.

Thanks!

Pete


My '84 pickup did that when the alternator brushes wore out. Don't know why
the other dash lights come on but replacing the alternator brushes fixed the
problem 100,000 miles ago. I got a brush kit for about $10 at the dealer and
did the repair myself.

Jeff Bertrand


Your response encouraged me to pull the alternator off my 89 pickup which also
had an intermittent problem with the charging system and brake warning lights .
I found the portion of the rotor where the brushes ride to be very badly worn,
well beyond specs, and I replaced the alternator thinking I'd cured the problem
. A few days later the problem reappeared and I realize now that I'm going to
have to look further into the charging system. The warning lights coming on
seem to be somewhat related to jolts from road surface irregularities and/or
wet weather. Can anybody suggest a logical next step for me in finding the
cause of this problem? Does this truck have an external regulator? TIA
Clint


I suspect the logic is as follows:

With the ignition on and the engine not running it is desirable to
have a lamp test. The oil light comes on as there is no oil pressure.
The BATT lamp comes on as the alternator is not producing any current.
The Brake light is forced to come on by a diode from the alternator
BATT lamp line. ***Thus any time the alternator isn't working the both
the BATT and the Brake light are lit; but if the Brake system detects
a fault only the brake lamp lights.***



I also found it very useful to connect a voltmeter to diagnose intermittant
alternator trouble. You can connect it via the cigarette lighter to monitor
as you drive. It should read 13-14 volts when the engine is running and the
alternator working properly. When the alternator fails, the voltage will
drop to 12 volts and below. The engine will stall if the voltage drops down
to about 8 volts.

Good Luck


---------------


I've got the "classic" brake light + charge light problem; car in question
is an 1987 Tercel (wagon).

A few months ago they started to flicker on and off -- time passed, they
stayed on for more time than off, eventually I wound up with the battery
dead in the middle of an intersection having to push it clear. No fun at
all.

Replacing the positive battery connector (which was pretty rusted) made the
problem go away for a month or so, then it came back. Replaced negative
terminal, ground connector from -ve battery to body, no improvement.

Checking things with a voltmeter, yup, the alternator was dead, no real
surprise so far.


Here's the annoying thing -- I replaced the alternator, and now while the
battery always charges and voltages are happy, the lights are constantly on.
This confuses me -- why would replacing the alternator make the actual
problem go away, but the warning lights stay there?


Things I've checked while trying to track this down that have been
recommended in this group in the past

Voltage across battery with engine off: 12.2v
Voltage across battery with engine idling: 14.5v

All fuses (in engine compartment and driver side door compartment) are
intact.

Alternator drive belt is tight.

Brake fluid is full. The light doesn't go off if I move the float up and
down, or if I disconnect the sensor, or if I disconnect the sensor and short
the other end of that connector with a bit of wire.

Voltages at the 3-pin connector on the back of the alternator:
12.2v on the white wire
11.9v on the black/red wire
1.6v on the yellow wire

12.2v on the 10mm wire screwed to the top of the alternator.

Connections that are good (with continuity tester):
-ve battery -> ground on body of car
-ve battery -> connector at bottom of engine
-ve battery -> engine case itself
-ve battery -> alternator mount bracket
engine case -> ground on body of car


Is there anything else I should be looking at? Is there something that's
likely to be wrong that I'm missing? Could I have knocked something loose
while replacing the alternator?


Any hints at this point would be very much appreciated..

thanks,


-- dan

According to my '85 4Runner (22RE) Factory Service Manual:

1.Drive belt loose or worn
2.Battery cables loose, corroded or worn
3.Engine fuse blown
4.Fusible link blown
5.IC regulator or alternator faulty
6.Wiring faulty

Looks like you eliminated 5 with the new alternator, I assume you
tightened the belts so 1 is gone, I assume battery cables are clean and
tight with the new battery, so 2 is out.

Looks line 3,4 or 6 to me.


Make sure there is a good ground between the engine and body. All kinds
of weird things can happen if the engine isn't grounded.


> Yup, I did that as well. Continuity checker between engine case and
>grounded point on the body comes up good, actually checking resistance and
>it's about 20 ohms, which counts as a good connection to me.

*******Hokey smokes, Dan! 20 Ohms is horrible! I'd expect an ohm or less
when read on a calibrated ohmmeter, that ground has to pass 200 amps
plus while you're cranking.********

Don't trust the accuracy of the $19 Radio Schlock Special if there's
big money riding on the accuracy of the readings. Accurate meters
that are properly calibrated (and can be occasionally recalibrated and
sealed by your friendly neighborhood metrology shop) are going to run
you at least $100, the nice ones start at $200. You can still get
good analog meters, but they're up in that price range also. Go get a
good Fluke or Triplett, something where you can trust the readings.

To really tell, clip the meter's red lead to a well grounded bracket
on the engine block (or the alternator mounting bracket), and the
black lead to the battery - terminal or hold it to the battery post.
Set the meter to a low VDC scale (20V, 2V or 200MV in descending
order, don't let the meter auto-range, by the time it reacts the
engine has started) and crank the starter to put a good load on the
battery. If there's more than about a 1 volt drop between the block
and the battery, there's a problem, find it.


--------------


Looking at archived posts on this, there's some discussion to do with
the alternator having to put out a certain voltage on the yellow wire to
turn these lights off; is there any way I can check this is happening?
What sort of voltage should I be looking for there?
??Will very bad things happen if I try and start the car with the
3-pin connector pulled out of the back of the alternator? I guess they
can't be that bad, because when the previous alternator was dead
nothing went too badly wrong, but I don't want to make anything worse..
??-- dan

Dan,

*****Remove the "charge" fuse--probably in the underhood fusebox which is
usually located near the battery. Start the car with the alternator
plugged in. You should get 12 volts at the yellow wire coming out of
the 3 pin connector on the alternator. If you don't, the alternator or
the built-in regulator is bad-not unheard of with aftermarket rebuilts.

To check the entire charging circuit, unplug the 3 pin connector at the
alternator, turn the key to the on position but do not start the car.
You should have current at all 3 wires on that connector as well as at
the larger wire that is held onto the alternator by a 10mm nut. The
yellow wire may be lower voltage than the others, that's normal. If you
have no current at all to any of the wires at the alternator, get a
wiring diagram and start backtracking.*****

You also may have a ******"charge light relay"******on that car, I don't remember
whether these were on 87 Tercel wagons or not. If it has one and it's
bad, the symptoms you report will occur.

"Dammit Jim! I'm an Automotive Service


--------------


I have a toyota PickUp 1983 model. I have starting problems everyday.
I need
to atleast try starting my truck for 15 minutes.When i do this I keep
hearing a click. Sometimes the car won't start at all (lights are all
ok in the dash)
and i just have to come back after 4-5 hours and try again.

Last week I was as usual trying to start when suddenly all the lights
in the dash just went off. I called towing and the towing guy told me
that I had to
replace a fuse. So he pulled a fuse from under the driver's seat and
placed it near the battery. I bought a new fuse and replaced the one
he had used.

My truck started immediately but the brake and charge lights are now
on all the time. I took it to a mechanic and he did'nt even open the
hood but looked at the
dash and said I have to replace the alternator and it will cost me
400$ totally.

I am just a little bit suspicious because I never had these two lights
on before I blew the fuse. I went to kragen and the had the electric
system tested. The battery is doing good but there is some problem
with the charging system (the
meter showed no readings only text such as "Battery good", "Charging
system not ok")

Please help me analyze this problem. I desperately need advice and
some pointers in understanding this problem. How can I test the
alternator again? How do I
know where the alternator is? Are there any pictures of where an
alternator is located in the toyota truck?

Thanks!
Deepa



Normal is around 12 volts with the engine off and it stays above 11
volts with the headlights turned on - if it plunges when you turn the
lights on, the battery is either severely discharged or going bad.

. Start the engine, and the system voltage at the battery should jump
to above 13 volts immediately. After the battery has had a chance to
charge back up from the starter cranking, you should climb to and hold
steady at 13.5 volts on a cold day, 13.8 to 14.0 volts on a normal
day, and it can climb as high as 15.0 volts on a very hot day

The voltage not going up on your car means it isn't charging - but
it could be the alternator, or the reference voltage and exciter
connections coming to the alternator from the car wiring - you need to
make sure the alternator is getting the proper signals to turn on
before you condemn it as bad. (Rare, but not impossible.)

Rick or Walter can tell you which pins to check for the incoming
voltage signals from the ignition key and the warning light circuits,
and which pin on the alternator to either ground or jump to the
battery (momentarily) to force the alternator to full field (maximum
output) - if you full-field the alternator manually and it starts
working it is probably a bad voltage regulator, if not it is going to
be bad brushes, bad diodes, or bad windings somewhere inside the
alternator. Time to find a good rebuilder.

--<< Bruce >>--
--
Bruce L. Bergman, POB 394, Woodland Hills CA 91365, USA
Electrician, Westend Electric (#726700) Agoura, CA


--------


Ladd Morse wrote,

To recap: Battery, Brake and Tail Light indicator lights on the dash
fail to turn off after the car is started.

=================================

Ladd,
All 3 lights are turned off by output from the yellow wire at the
alternator's 3 pin push-in connector.

Check the "charge" fuse in the fusebox under the hood, near the battery.
If it's ok, chances are the alternator is no longer charging.

If the car starts, it is safe to drive but is running off the battery
only, so all possible electrical stuff should be turned off. Eventually
the battery's available voltage will drop below about 10 volts and the
engine ecu will shut down (won't be damaged however).

When you get the car home, unplug the push in connector from the
alternator and turn the key on. With a test light, check for current at
all 3 contacts in the harness end of the connector. 2 should make the
test light glow brightly and the remaining one should make it glow, but
only dimly.
If this checks out, you need a new alternator.

"Dammit Jim! I'm an Automotive Service
Technician, not a mechanic!!"

Steve S.


----------


I ran across this post this morning on Google Groups and it saved my
ass. Both charge and brake lights on at the same time = bad voltage
reglator or alternator. 88 Toyota 4x4 pickup 22RE motor

<a href='http://groups.google.com/groups?q=charg ... .ca&rnum=1' target='_blank'>http://groups.google.com/groups?q=charg ... &rnum=1</a>

I thought it was a bad battery at first, but the battery was smoked
by the 17+ volts coming in from the fried voltage regulator. I
couldn't find any voltage regulators at the local auto parts stores,
so I got a new alternator with the regulator built in and it works
great and back to 14.2 volts.

Can't complain, first malfunction other than clutch or brakes in
130,000 miles.

Being a novice at auto repair this information was invaluable to me
and I thank you all for the help.

Terence

----------


Question: 1990 Dodge Spirit 2.5 l mileage: 70,000. Hi, ****my alternator over charges- periodically it puts out about 18 V and I can hear the battery sizzling.**** 1. I have swapped out the alternator- makes no difference (so the alternator is not the problem). 2. I have swapped out the battery- makes no difference. 3. Last Dec. I replace the computer so I would like to think this is not the problem. 4. I have checked the wiring harness. Any ideas?

Answer: Your problem may be simple like a ***loose or poor ground wire.*** On the other hand, maybe not. The voltage regulator is part of the computer. We have on occasion installed an external voltage regulator, not using the computer to control the voltage from the alternator.


Question: 95 Pontiac Grand Am 6 cyl. 3.1L mileage: 153000. My car's battery died. Then I replaced the battery and the voltage gauge on it; reads really high now. ***It’s at 16 1/2 to 17 volts when it’s running.*** I took the alternator to be tested and they say its fine. What do you think the problem is? Thanks!

Answer: We have found that the voltmeter gauge on the dash is not very accurate. With the proper equipment, test the voltage across the battery with the engine on fast idle. ***The voltage should read between fourteen and fifteen volts. If it reads higher or lower, check for loose or bad ground connections from the engine to the battery.*** If okay, your voltage regulator in the alternator may be faulty.

------------

> When I bought a new alternator, the "tech sheet" which came with it
>said that unless there is 12v. at the "L" connector (one of three
>wires in a plug which plugs into the alternator) when the ignition is
>on, replacing the alternator will not correct the problem. The 12v. is
>not at this connector.
>
> I have checked all fuses and fusable links, cleaned and reseated
>all plugs near the battery as suggested in this tech sheet, and still
>no 12v available.

As I posted before, in my 85 Celica the "L" terminal provides the field
current that the alternator needs to get started. No initial field current,
no go. The current comes _through_ the brake and charge system warning lights
in the dash. That way they light before the engine is started (I assume it
means a charging system failure would also light the brake warning light.)
There are also a couple of diodes and the 7.5A "charge" fuse in the circuit.

I'm not sure because the schematic is at home, but I think if both those
warning bulbs were burnt out, there might be no current at the "L" terminal
and the alternator would not work. This was not so in my 83 Tercel which
had a resistor in parallel with the charge system warning light, but I could
not find this resistor in the Celica schematic.

If the wiring itself is bad, just do some kludge wiring in the fuse box under
the hood... a couple of dashboard indicator bulbs in parallel connected
between the "engine" fuse and the "charge" fuse will provide the necessary
bootstrap current. That is the hack fix I did on my 83 Tercel and it worked
just fine that way until I junked it a year and a half later.



It will still work without the power to the L terminal, this system uses
in IG terminal also, they both do the same thing, one is a backup incase
of bulb failure, the IG and F terminals go to the trio (to excite) the
only difference is the IG has a resistor built into tha alternator to
keep the trio from backfeeding into the system, the L uses the bulb to
knock voltage down to prevent backfeeding. Some systems use a 3rd wire,
this is a "S" terminal for sense, and it determines voltage at the
battery to set regulator output, will work without any power here, but
voltage will be a bit high, around 15+ volts. In reality, if you revved
the engine without anything except the big white power wire going to the
battery, it would excite using just residual magnetism in the rotor.
Try it, kinda neat!!!

--
Rick, Toyota Master/ASE Master

----------------

My 82 Supra has had a surging voltage on the dash guage for a long
time. Would swing from about 12 to 15 volts whenever the engine RPM
was over about 2000.
That wasn't too bad and I didn't worry about it as long as the
battery was charging. Well, it isn't any more!
Now the voltage guage is swinging wildly when the engine is started
and the lights/horn, etc. are weak, indicating that I no longer have a
charge going on.
I was going to replace the alternator, but got a tech sheet with
the alternator which said to check the voltages of the wires on the
plug which goes into the alternator. All are supposed to have 12v
going to them when the ignition switch is on, and two of them don't..
The tech sheet says that if these voltages are not correct or missing,
replacing the alternator will not correct the problem.
So far I have checked the battery connections, the charge light
relay, all plugs located around the battery, the fuses both in the box
in the engine compartment and in the left kick-panel. When the
ignition switch is on, the alternator light is not illuminated on the
dash.
Help! I am not exactly rich, which is what it takes to visit the
local Toyota dealership and their reputation for repair is horrible,
to say the least.
Thanks in advance!


Check your fusible links. These look like wires but are designed to
act like a fuse when the circuit is overloaded. On my 83 there are
five of them, ***Two in the engine fuse box, one coming directly from the
battery into a connector, another one built in that connector and one
in black box next to the connector. *** I do not know which ones they are
but three of them are in the alternator circuit. According to my
wiring diagram, they are, fusible links 0.3p located in the engine
fuse box, 1.0y located in th engine fuse box and 2.0l located in the
connector or black box.

Jim


What worked for me with an 83 Tercel, was to go to the Toyota dealership
and ask nicely, and they let me look at the service manual and even photocopy
out the electrical schematic.

I have in front of me the Haynes schematic for a "typical 82-85 Celica"
which happens to be exactly right for my 85 Celica. The alternator circuit
is similar to that in every other car schematic I've seen where an alternator
with built-in regulator is used.

Such alternators have three important connections: Ground, power out, and
startup power in. The alternator initially requires some current on the
"startup power" wire to energize the regulator and field coil. Once it
rotates and generates power, it powers itself and no longer requires the
startup current.

The startup current is supplied through the dashboard warning bulb, among
other things. If the alternator fails to start powering itself (i.e. work)
it continues drawing startup current and the bulb continues to light.
In the Tercel there was a resistor in parallel with the bulb. In the Celica
there is some kludge involving diodes and other bulbs to serve a "lamp check"
function (i.e. warning lights all light before you start the engine.)

Anyway what it comes down to, is the startup current is supplied through
the 7.5A "charge" fuse. Pull that fuse, and neither the alternator nor
the warning light will work. Have you examined it carefully? Sometimes
they are blown even though at first glance they look good.

Continuing with the Celica schematic, the alternator gets...
- the startup current (7.5A fuse) through yellow wire on terminal L
- direct battery connection (charge current) blue wire, terminal S
- another direct battery connection through white wire,. terminal B
- switched 12V (ignition on) through 15A "engine" fuse, through
blue/yellow wire on terminal IG (note: this fuse being blown
would _not_ prevent the engine from running, in fact the fuse
serves _only_ the alternator. Don't ask me.)

So yes, with the ignition on, every single wire plugged into the alternator
should show +12V on it when unplugged from the alternator and measured with
a voltmeter. I don't know why they made it this complicated.

Note, there are assorted "fusible links" shown near the battery which
I haven't mentioned above.

You can always take the alternator out and have it tested. Around here the
big Canadian Tire stores have alternator testing machines right on the
parts counter.
Give a boy a gun-give a biatch a cell phone-and pretty soon you almost got yourself a police state.

Orwell said: War is peace! Freedom is slavery. Ignorance is strength...

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