One of my rad fans has stopped working...

[thom4782]

With your clarification try these things...

1) Set the internal car temperature to as low as it will go. Start the car and turn on the AC. Get out of the car and move to the front so you can hear the fans. Both should operate in low speed. If neither fan is running in low speed, then I would guess both low speed ballast resistors are broken. This was the case for my car.

2) If you find in step 1 that one fan runs in low speed and the other doesn't, turn the car off and switch the low speed fan relays. Then repeat step 1. If the fan that didn't run in step 1 starts running and the other one stops running, then you have a bad relay. If the fan that did not run in step 1 still doesn't run, then that fan's ballast resistor or the fan motor itself is broken. Steps 3 and 4 will help identify if its the motor.

3) Steps 1 and 2 focused on low speed operation. Step 3 and 4 will test high speed. Begin by switching the high speed fan relays. If the fan that does not work in high speed starts working after the switch and the one that worked originally stops working, then the relay is the problem and you'll need a new high speed relay. And you will have ruled out a broken fan motor.

4) If the fan still doesn't work in high speed, then you'll need to jump the high speed relays as described in the URL I posted earlier (thstone's post shpws a picture). After jumping the relays, if the fan still doesn't work, you probably have a bad motor. To finally sort this, you might have to test voltage at the fan motor.

Hope this is more helpful.

[pothole]

Thanks guys. How much do the relays typically run. If they're cheap, first step might just be to replace those...

[AKnowles]

Originally Posted by pothole

Thanks guys. How much do the relays typically run. If they're cheap, first step might just be to replace those...

First step should be just to test them via the touch and click method thstone mentioned. Really, it's pretty easy to do. Did mine this way trying to figure out why my drivers side fan would not work in low speed.

If you plan to keep the car though, get a Durametric or used PST2/PWIS so you can perform better diagnostics and turn on functions like this. It'll be worth the money you'll save going to the dealer the first time you use it.

[thstone]

Originally Posted by pothole

Thanks guys. How much do the relays typically run. If they're cheap, first step might just be to replace those...

The relays are cheap ($10) but its almost never the relays. That would be too easy and too inexpensive.

[pothole]

Thanks, I'll probably bag a relay or two just to be on the safe side!