radiator fan

I have a 93 automatic honda accord. The radiator fan is not coming on when the car heats up. The internal tempurature gauge is working.

Can someone give me a troubleshooting outline for this? What are common causes?

Thanks,

Tony

by internal temp guage I assume you mean the one in the dash??? If that's the case then the one under the hood is broken. Nothin else goin on? Does the car regularly overheat? If the car overheats and you then turn the heat on full blast (i suggest you open the windows) does it return to near normal temperature?

Yes, I did mean the dash gauge.

After playing around on the car, I have done the following...

If I turn on the air conditioner, both fans work.

If I disconnect the 2 pin thermoswitch and short the harness connectors, the fan does not work. However, If I leave the harness connectors shorted and turn the car off, the fan comes on (!?!).

With the thermoswitch harness still shorted, Pulling the relay labeled "cooling fan" in the fuse box does nothing, no clicking. Replacing the relay with the one next to it, which is same part number and nothing happens either.

Any thoughts???

Help?!

THanks,

Tony

Well, you haven't answered the most important question:
Does the car regularly overheat?

Because if it DOESN"T, then nothing is going on. The fan doesn't run unless it needs to. With the A/C off and at moderate highway speeds, I doubt it would kick in.

Well, yes the car is overheating, but only in slow traffic or if driven for awhile. Second, if the radiator fan switch (thermoswitch) is closed (or the connector is shorted) then the fan should kick in immediately. This isn't happening unless the car is off.

Then if it comes on with the A/C (which you say it does) it isn't the fan relay. Sorry. The I guess the last possibility is the temp sensor (or did you say that was OK?)

If I'm understanding all the checks you've done, and assuming you are correct in your assumptions, it seems that the power to that fan is open-circuited with the key on, and there's no power feed, but it does have the direct battery feed with key off (as it should have). The question is, if you drive it around until it's good and hot, will the primary fan come on by itself and run for a while once you shut it down, or are you saying that the ONLY way to run it is to shoot power to the relay w/key off?