83 Tercel Sedan cooling fan problem

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kitchman
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Posts: 173
Joined: Mon Jun 20, 2011 12:24 pm
My tercel:: 1983 2wd tercel hatch back ,1986 SR5

83 Tercel Sedan cooling fan problem

Post by kitchman »

Hello all, I figured before I reinvent the wheel I'd put this problem out there.
The fan runs fine when 12 volts is applied directly to the motor. All fuses tested good, The fan relay in the engine compartment fuse box was found to be defective and since replaced. I removed the connector from the fan temp. switch in the radiator. When the leads from the connector are jumped the new fan relay is energized and clicks but the cold mixture heater relay also is energized and clicks? The ground connection to the fan motor is good. even when the fan relay is removed and terminals 3&4 are jumped the same thing happens and no power to the fan motor is delivered. Has anyone been down this road before?
Thank you in advance
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helipilot77
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Posts: 382
Joined: Tue May 03, 2016 9:03 pm
My tercel:: 1984 SR5 wagon
Location: Seattle, WA

Re: 83 Tercel Sedan cooling fan problem

Post by helipilot77 »

So when you jumper the fan relay to click it on you are not reading any voltage on the fan connector? If you look at the. Wiring diagram you can see that it is being switched by power coming from the 7.5amp Ign fuse. But the power side of the relay is powered by the 30 amp fan fuse. I would recommend checking that you have power coming into the black/blue wire on the relay. If you are make sure it is also coming out of the black wire on the relay that leads to the fan. You might have a bad contractor in the relay if you replaced it with a used relay. Good luck!
. / TOYOTA
./_| |/|/ |]
kitchman
Top Notch Member
Posts: 173
Joined: Mon Jun 20, 2011 12:24 pm
My tercel:: 1983 2wd tercel hatch back ,1986 SR5

Re: 83 Tercel Sedan cooling fan problem

Post by kitchman »

Thanks for the reply!
As I stated all fuses/relays check ok. When the ignition is switched on, power is supplied to either terminal 3 or 4 I forget which. The other day I checked for continuity between the black side of the fan connector and the relay terminal 3 or 4 which is energized by the action of the relay and there was no continuity. Still wanting to know why the cold mixture heater relay is activated when terminals 3&4 of the fan relay are jumped. I only have FSM for my 86 wagon which shows a black wire supplying power and a brown wire for ground. On my 83 sedan the ground is white. Any way wish I had a good wiring diagram for the 83. Thinking at this point to split open the engine fuse box and figure out why there is no continuity as I described.
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helipilot77
Top Notch Member
Posts: 382
Joined: Tue May 03, 2016 9:03 pm
My tercel:: 1984 SR5 wagon
Location: Seattle, WA

Re: 83 Tercel Sedan cooling fan problem

Post by helipilot77 »

Yeah sounds like the problem lies in the wire that travels between the relay and the fan connector. Double check that the connectors on both ends aren't corroded and that they have good spring tension to make contact on the terminal blades.
. / TOYOTA
./_| |/|/ |]
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