Coolant fan failure on 1992 Grand Am SE?

[Troy1992]

Hi,
My Grand Am started overheating yesterday while idling in a parking lot. The gage almost got into the red area. I quickly got it back on the highway and it cooled back down to normal. When I got it home I raised the hood to check if the fan was running, it wasn't. I already had my air conditioning on, but it didn't make any difference. I gave the fan a spin with my hand (after car had been turned off and had cooled down) and it spins freely, I would think if it had burned out it would be stiff to turn. I checked the fuse, it's fine. I suspect the relay that controls the fan has failed. Would it be okay to disconnect the plug on the back of the fan and use either a test light or digital multi meter to check for voltage? I've been told that there are some circuits on a car that you shouldn't use a test light on.
Also, if it turns out to be the relay, where is it located and how difficult will it be to replace?

Any help & advice would be greatly appreciated.

[rixGAphx]

You are incorrect to think that a faulty fan would be hard to spin. That would only occur if the bearings failed, and you would usually have heard them screeching before failure.
Fans *usually* fail electrically, either the windings or the commutator. These will not affect free-spinning if they fail.

Could be a bad fan motor, or the relay.

The relay is one of several, located in the engine bay, passenger side, above/behind the firewall in a small recess.
Plastic boxes, about 1.25x1.25x2 inches, black or light green or gray.
There's also a fuel pump relay and an A/C relay there.
I don't know which is which for your vehicle.
Do NOT unplug any of these while the key is 'on', as disconnecting *may* send a fault code to the ECM.

You could unplug one, then see if it controlled the fuel pump by turning the key.
Test the next to see if the AC still works.

Once you've identified AC and fuel, the remaining relay is Fan.
Continuity testing of a relay is easy if you've done, but impossible to describe.
Also, they only cost about $15.

If you TOTALLY unplug the fan, you can safely test for continuity.
You can even do a shade-tree mechanic's continuity test: ground out one terminal, and hot-jumper the other terminal (with a 30 amp inline fuse for safety, of course :D ).

Good luck.
-Rick

EDIT: Sorry, the above-described location for relays is accurate for my '96 3.1.
For 3.3's, Chilton's says they're located in the middle of the engine bay, at the top of the firewall.

[Troy1992]

Hi Rick,
Thanks for the suggestions. I went ahead and disconnected the plug from the back of the fan and checked for voltage using my multi meter. With the key on (engine off) and the air conditioning turned on, it read zero volts. I haven't tried connecting jumpers to the fan yet, but being that no current is on the plug I'm willing to bet the fan is okay. I think I will just try to get a new relay and install it and see if that fixes the problem.
I looked on the middle of the firewall but don't see anything that looks like relays. Could they have made some kind of enclosure for them all? Hope someone can point me in the right direction.

Thanks Again,
Troy

[RocketFast321]

it could be a temperature switch or dang it can't think of the other one. We have been selling them left and right at work. For a temp. fix you could rig a switch up for the fan in he car.

[rixGAphx]

Originally posted by Troy1992
Hi Rick,
...checked for voltage using my multi meter. With the key on (engine off) and the air conditioning turned on...
Well, it SHOULD read zero under those conditions!
The fan only comes on when 1) the AC is on and2) the engine is HOT.

I looked on the middle of the firewall but don't see anything that looks like relays. Could they have made some kind of enclosure for them all? Hope someone can point me in the right direction.
I don't know what else to tell you. That's where Chilton's says they are, and of course, Chilton's is never wrong :roll2:

Good luck.
-Rick

[Troy1992]

Well, I spent an hour and a half looking for the relay and I never did find it. I'm not sure whether GM did a really good job of hiding it or maybe I'm going nuts! Anyway, after I plugged the fan back in and was getting ready to call it a day something just made me crank the car to try it and, IT'S WORKING AGAIN!!! I don't know whether the contacts on the fan and plug were just corroded and the act of unplugging and plugging it back in cleaned them to make contact, or if the problem still remains and is just intermittent. I guess time will tell.


Originally posted by rixGAphx
[B]Well, it SHOULD read zero under those conditions!
The fan only comes on when 1) the AC is on and2) the engine is HOT.

[B]


Yeah, I didn't know that the AC compressor had to actually be engaged for the fan to be on. I thought if you turned the key to the run position (without cranking the engine) and had the climate control selector set to MAX, NORM, or BI-LEVEL the coolant fan would just run continuously like the blower motor does. I didn't realize that they set it up to cycle on and off with the AC compressor.

I'll get out and drive it around in town tomorrow and see how it does. I'll try and run without the AC on to see if it works that way too. I hope this is the end of this problem, either way I'll post back in a few days with the outcome.

Thanks again guys for your help.

P.S. If anyone now or in the future knows where GM put that blame relay I'd appreciate you shoot me a PM to clue me in. Even if it makes me look stupid for not seeing it already. :D