csmab

My rear blower motor isn't coming on after driving in the dreadful 100 degree TX heat. I know it should run around 20 minutes after the engine is turned off when it is this hot. The blower fuse in the engine bay is good. The blower relay has also been changed. The fan works when I engage the heater at both low and high speeds. Today when I unplugged the rear duct temp sensor the fan came on and ran for 20 minutes and then shut off as it should. Based in this can I assume a new temp. sensor will solve my problems? Is this an easy DIY replacement? It looks easy but I have gotten over my head on other items that I thought looked easy. I also noticed that at the end of the 20 minute cycle run the blower motor started giving a high pitched squealing sound. A new fan is pretty expensive. Does anyone know where I can find a rebuilt blower motor?

Thanks

csmab

Anyone???

SuperUser

I bet you could buy a used fan from someone that did the RS bypass tube.

2Many Cars

Unless the fan cage is rubbing on the housing (unlikely) it sounds like a bearing in the motor is about to go. Try putting a little light oil on the bearings at each end of the motor shaft. It won't last but if the noise goes away it helps identify the motor as needing replacement soon. I'm not that familiar with the temp. sensor but a little electrical sluthing should tell you what you need to know. Test for continuity in the sensor both hot and cold (it should be a simple on/off sensor). If you're getting the same reading at both temps then it's bad.

Bradford

csmab, got your e-mail. I had the same problem and it ended up being a fuse. On the driver side of the engine compartment there is a small fuse box. I replaced the fuse in there that went to the fan and now all is good. Good luck.

csmab

It looks like I can buy a Bosch blower motor if I determine that mine is bad for $155. The original Behr motor and fan is $476.

http://www.partsgeek.com/catalog/199...wer_motor.html

I assume you can replace the motor without replacing the fan/motor/assembly. The key is to get the motor to run after shut off when hot. I will take some temp. reading in the ductwork this weekend to see if they are above 175 degrees which triggers the fan. I can't imagine that the temps wouldn't be over 175 when it is 100 degrees outside after 30 minutes of driving.

csmab

Thanks Bradford. My fuse is good. I was hoping for a simple fuse or relay problem. I have a new temp sensor coming so we will see it that fixes the problem.