strange AC behavior
 

Hey,

So for the past few days my climate control has been going haywire. Here are some highlights:

- will stay on after i turn the car off (i then have to turn the car back and off quickly to get it to go off)
- It will behave normal-ish for a bit but then studder or pulse lower (fan speed) when i am coming to a stop.
- If i change controls (when it is pseudo working right) there is a long delay before going to the fan speed setting i select... so if i set it to blast it will follow in a few seconds and vice versa.
- Currently it is stuck on about medium speed and blowing cold (thankfully since its hot here).

The digital display looks normal and there are no fault messages showing up anywhere. If any of you have a sneaking suspicion of what might be going on please chime in. I am hoping this is just something simple and cheap like needing a new battery.

blower fan speed regulator. Not super common but i have replaced a few for fan speed acting erratically. Its pretty simple to change. pull the glove box down and its staring right at you. You will need a t-20 torx driver and a 5.5mm socket. It will set a fault in the a/c control module but no lights will come on in your dash telling you so.

Thanks for taking the time to chime in. What do you think would account for the momentary slowing down of the blower speed when coming to a stop? It's very brief. Hopefully all this erratic behavior is all just the regulator. The blower motor itself makes squeaks at certain speeds so perhaps I should do that too.

My A/C also act up the same problem similar to your last listing. The fan would only blow as high as three bar level when set to full blast, but blow cold as well. Going to take the truck in to the dealer this Friday. Vehicle is still under extended warranty. Will let you know what the dealer diagnos. Hopefully my warranty will cover for this. I'm sure it will cause this is an electric component issue.

FYI, if you don't have a 5.5 mm socket the 7/32nds is very close (5.556 to be exact) and works just fine on lower torque bolts (and nobody is going to use a 5.5 bolt in a high torque situation anyway). This is the same bolt/screw size used on the 955 cabin filter cover too.

5.5 mm is quite common on BMW's too.

thanks for the tip!

Alright, I ordered a blower regulator and a blower motor. Looking forward to attempting this fix when they arrive.

YES! My regulator came today (not the blower motor yet - which still works but is sometimes noisy) and i got the glove box down and replaced the regulator. SUCCESS!!! Everything is working as it should again. BIG THANKS to Tsmith84 for the correct diagnosis.

The only stressful part was removing the trim piece because i thought it was going to snap in half. But I slowed down and pryed it off. So yeah $90, a beer, some cheering spectators (the wife and daughter), 30 minutes and some wrenching later. Boom.