need some help here please.
We recently purchased a 91 Accord, that has developed a problem with the cooling fan. It seems the radiator fan will turn on and run until the battery is dead, but this only happens occasionally. I have recharged the battery a number of times trying to figure out the problem. I have replaced the coolant temp sw and sensor on spec (one on the water pump & the other on the therm housing) and that did not cure be the problem. The car ran fine for 10 days before the battery was dead again.
Borrowed the Chilton manual from the library. Seems this car has a cooling fan timer unit, although when i was at the dealer pricing the switches, they said it does not have one. Where would the timer be located if it did have one.
Any other ideas where to look.
thanks for the help!

 

We've recently had this, just search a little and you will find it.

 

I had the same problem with a 93 accord a few years back. I had a diode that was bad in the fan timer unit. When I replaced the diode in the fan timer unit under the sterring wheel, the problem was corrected unitl recently. Now my Radiator fan does not work. I went to the salvage yard and got a fan timer switch. That switch did not work either. I then jumped the fan straight to the battery and it would only work if I put the negative to the positive of the battery. Then the fan turned opposite of the condensor fan. The condensor fan turned clockwise and the radiator fan turned counterclockwise. Earlier in the year I had changed my condensor fan because it was blowing fuses. AFter I changed it I saw no problems until this one surfaced. I think the radiator fan shorted to ground from 250,000 miles. I am going to connect my new fan to the battery tonight. If that works, I know I probably got a bad fan timer unit from the junk yard.

 

the fan relay is located in the fuse box under the hood

 

We swapped the fan relay with the power window relay just to prove that it was not the relay itself. No luck. I will give the wrecker a call and see if he has a timer unit and see if i can locate it under the steering wheel. Where should i be looking under the dash, is it fan marked timer.

 

yay, me to the rescue...





Test it first to make sure it's busted, it's a $135 part new. Good luck

 

Also don't forget about the temp sensor.

I had the opposite problem, my fan wasn't coming on after a hard drive, and pulling up to the house and stopping. Sometimes it would go on, then off, then on, of, and click back and fourth. Thought it was the relay located in the fuse box under the hood, swapped it for the power window relay. Windows still worked, and the fans kept sputtering on and off.

Then learned the fans are controlled by the cooling system, aka, where the coolant runs through your engine block. There are two connectors to temp sensors on the engine block. One is located next to the thermostat on the back of the engine, near the distributor, the other is located in the front of the engine, where the upper radiator hose enters the engine.

Here's how to check, get a paper clip, and bend into a "V" shape, so you can stick one end into the green plug. Wiggle it around if you don't make contact. You are basically by-passing the temp sensor (a basic switch if you will which tells the car to turn on the fans or keep them off). Think of it this way, if the temp sensor feels the car is hot, it tells the car to turn the fans on. Now in your situation, maybe its stuck open?

I dunno, try the paper clip method on both plus, one of the back of the engine, and one on the front.

Gotta go to class, will check back in about 4-5 hours. Sorry if not all the info is here, PM me for more info. I have my old temp sensor at home, and can take pics of the areas where they are located.

 

The fan is located under the sterring column on the Drivers Side. I brought one from the dealership yesterday for 140.00. When it broke before, I took it apart and replaced a diode. It worked fine for another 50,000 miles and went out again. This time the Toshiba timer inside the timer module had melted.

 

I did not get a chance to spend much time this weekend on the car, but found the timer hidden behind the remote starter unit. Daughter took the car to school today and of course it died in the lot. Soon as i put a booster cable on it the AC fan started to run. Boosted it and drove home, opened the hood, the AC fan was off and radiator fan was on. Rather than let the battery run down, i removed the radiator fan relay. Then reached under the dash and disconnected the timer, then reinserted the relay, fan stopped running. I do not like doing things this way because you never really get anywhere. Calling for rain & snow so i likely will not get another chance till the weekend.

To cover my corners, here is a question. The wiring diagram in Chilton and Haynes shows a condensor fan relay and radiator fan relay, although in the fuse box under the hood there is no condensor relay and nor is there anything on the plastic cover to indicate this car has one. However, there is a socket that does not have a relay but the fuse cover has it crossed out to indicate not used. If this car has no condensor fan relay, how does it work. I guess it can get confusing when a schematic covers several years and options on cars.

Rather than become confused, i disconnected the fan timer and let my daughter take the car to school till the weekend. Then i will check the timer unit carefully & go from there.