2001 C2 with 90K miles: while testing activations on my Durametric, I was surprised to discover that both rad fans were not working on stage 1 and only the right one in stage 2. I checked the fuses and relays and based on the comments in this forum I went ahead and ordered two new fans. Got them installed over the weekend and good news, they both now work in both stages so I presume it was the resistors that failed on the old fans. My issue is that they did not come on stage 1 as expected when I turned on the a/c.

My question is: is there a minimum ambient or engine temp that also affects fan operation with the a/c turned on? The ambient temp was approx 40 degrees F and I was just moving the car in the garage so engine was not up to temp.

Thanks!

 

No minimum temp.

Why did u get new fans? The replacement resistor from amazon is $10. A shop would be less then a hour to fix or do yourself.

Pic of new and old resistors

 

I considered just changing the resistors but didn't trust my soldering skills under the car with the winter driving conditions - salt, slush etc. up here. Removing them to solder on the bench was an option, but they were not too expensive on RockAuto (less than $100 each for Uro ones) and the old ones were original to the car with some corrosion so I thought it was better to replace.

 

Well, you got all the right stuff done and apparently the fans are now working on both stages. So that leaves...why do the fans not come on stage 1 when you put the AC on. Like he said, no minimum temperature. In fact the defroster will use the AC system to help remove moisture from the cabin, even if it is cold outside. Perhaps a little more testing. Put HVAC on lowest setting, then hit the AC button and see if the fans come on. Second, put the windshield defroster on, turn everything up to the highest temperature (warm/hot) and open the engine lid and see if the AC compressor is engaged (spinning). Actually you should do this in both scenarios to ensure the AC compressor is engaged.

 

Agree with replacing the fans, because, well, they are already 20 years old. But yeah, the resistors were the fault. No minimum temp for stage 1 as indicated by De Jeeper.

 

I sometimes forget how nice a heated garage with a lift. Not a bad price for the fans, cheaper then the factory resistor.

 

I was able to take it out for a nice run tonight to warm up the engine even though it was only 30 F outside. Roads were dry and empty so I put on about 30 highway miles.

So I had the defroster on with the a/c and when I got home the fans were on, working fine. Engine was at 180F and the fans stopped when I turned the a/c off. Came back on with the a/c so all is well.

Thanks for the help!