My 86 GT has some cooling problems, mainly the previous owner knew nothing of cars. Heres what I discovered today. He cut the fan cables one black one black with white stripe and hard wired it to a toggle switch.

I tried some troubling shooting. I turned on the ac and checked for power at both wires, none at all. With the ac on the air fan in the trunk runs. Never knew it was even there. The fuse is good. I know there is a sensor to turn it on. I don't know where it is located at. I'm sure there are some relays also.

Could someone point me to some links or other help full info.

Any help would much appericated

Thanks

bump I need some help guys

bump for ya... if the back one turns on but not the front, i'd say it's somewhere around the front relay under the driver's side headlight.

That relay up front can go bad, I've had 2 bad ones personally. One that just didn't work, one that stuck on until you tapped it with something. The bad one had a toggle switch wired in, with the wires running through some jagged holes into the interior, and no rubber grommet. Fire hazard? What fire hazard?

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Bob Williams
Multi-colored '87 Mutt, a work in progress! (3800SC installation in super-super-ssuuppeerr-slow-motion progress... Well, it used to run... Stupid... Axles... Argh...)

This might help you.

There are two sensors, and two coolant temp switches on the 2.8 engine.

Directly above cylinder #5 and right below ignition coil, threaded into the block is the coolant temp gauge sender. Its only purpose is to send temp info to your gauge only.

Look directly below the thermostat housing, there will be a temp sensor right there. It is for the ECM.

To the front (towards front of car) of the thermostat housing will be the fan switch and the cold start injector switch.

The fan switch has a round 1 wire connector on it, while the cold start injector switch has a connector on it with a wire spring clip exactly like the injectors have.

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jetman
Silver 86 SE 2M6 4-speed, with "check wallet light"

On top of that, I believe the ac relay is by the fuel pump relay on the drivers side of the firewall, and the fan relay is under or near the drivers side headlight. The A/C relay should have a dark green wire.

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Calgary - August 1, 2004 Fiero Fiesta
@ SouthCenter Mall

[This message has been edited by Comealongway (edited 03-18-2004).]

I was looking at the headlight and around them and found this:

If you are in the drivers seat the wires are just to the right of the drivers side head light. Is this related to the fan or the head lights?

Aren't those the wires that plug into the cooling fan relay?? I think that's what they look like. Been a while since I had to do anything down there. I don't have my factory manual with me, or I'd look the colors up for you. I just can't remember if there are 2 plugs that plug into the relay, or 1... I thought it was 1, but maybe different years...? Still, you're missing something there no matter what it is! Edit: Doh, those are the wires that plug into the headlight relay. Forgot about the pre-87 headlights. The cooling fan relay will be in front of the driver's side headlight, screwed to the metal wall directly in front. Should have 1 plug with 2 large wires, and 2 small wires.

[This message has been edited by Riceburner98 (edited 03-18-2004).]

Damn, there are relays hidden all over this car! I have a question. There are two wires to the fan, one black the other one black with red stripe, I'm assuming one is ground the other hot. With the key on and ac on I get no power to either one. The fan in the trunk does blow, makes a hell of a racket. Does the relay control both of these? I can take the relay out and check for power with the ac on but I don't know which wire should be hot. Any ideas?

The black one is ground. Black with red stripe goes through the relay to a fusible link for power. If you ground the black wire and put 12 volts to the black/red, the fan should run.

I did some trouble shooting this morning, I took off the Fan relay in front of the right headlight. I put the car in diagnostic mode which should make the fan run. I checked the plug that goes into the relay. Moving left to right, the first two wires had power, the thrid wire (being grounded with my test light) turned on the cooling fan in the trunk. Also when the car warms up enough the trunk cooling fan will turn on.(Does the temp switch contol the trunk fan and the cooling fan) The fan does work, I checked the fuses and changed them just to be sure. Is it possible for the relay to be 1/2 bad? What else could cause my fan power wire not get power in diagnostic mode?

Sounds like a bad relay... From what I remember, there should be 2 large wires, 2 small. The large wires are obviously the switched one - one should have power, the other goes to the fan. Then the 2 small wires - one should have power, the other (green?) is from the coolant fan switch on the engine, and a GND on it turns the relay on. Try this: Normal engine mode (not diagnostic), Key on - engine off, take a jumper wire and ground the small wire (green?) that doesn't have 12v on it. You should hear the relay click and the fan come on. If the relay clicks, and fan doesn't come on, either bad fan or bad relay. If relay doesn't click, bad relay or bad connection. You can also disconnect the relay from the wiring, then with a large jumper wire connect the 2 large wires together. Those wires connected will turn the fan on, assuming your fan and fuseable link are good. Wish I had my manual on me so I could check colors for sure! - Bob Williams (Oh, and the trunk fan has it's own relay, attached to the fan itself. So the front one can be bad and that one still be good.)

Hey RiceBurner98,

I finally got around to getting a relay, and after fixing all the wires the previous owner hacked up, Presto! The fan comes on at 220F. Its hard to beleave the previous owner cut the power wire at the fan and ran wires to a switch, when an eight dollar relay fixed the problem.

I still have one ? Does the Diag. mode turn the fan on? When I jump the connecter the fan does not come on.

Right now I am just happy it turns on when the motor gets hot.

Thanks for your help

Not sure on the diag mode thing... If the rear fan comes on then the front one should, but I can't say for sure either way. Anyone? Should come on when the A/C is turned on, car running or not.. That's the usual test.. Good work! You saved another Fiero electrical system.

The ECM only controls the fan on the DIS cars, the '87-'88 L4 motors. On all the V6 cars and the early L4 cars the fan is only controlled via the relay and the temp switch in the head, with an additional circuit that turns the fan on with the A/C regardless of the temperature.

JazzMan