ehanauer

This morning 3 of the 4 AC vents were blowing ambient or warm air. Only the far passenger side was blowing cold.

I parked the car while in a store for about a half hour. Upon starting, all the vents blew cold. I parked again for around 15 minutes, and again all were blowing cold air.

This seems to be some sort of glitch in the mixing valves. Was the instant cure like rebooting a computer, or is this problem a portent of problems to come?

Has anybody else experienced this?

ToreB

You describe a normal scenario of failing mixer or fresh air servos. The internal motors wear out, short circuits, and kills the movement limit switch. This will stop the motor/arm at a certain point of travel. The Climate Control Unit senses the lack of movement and shuts down the servo until the ignition has been off. It then tries again to move the servo, and it can be OK for a while, just waiting for the arm to get to the same damage point in the limit switch. All details on this here.
Cheers,
Tore

ehanauer

Thanks, Tore. Sounds exactly like what's happening. I'll just live with it until it fails completely. Glad it's not serious, because the evaporator was replaced just a year ago.

destence

You are amazing Tore.

ToreB

Thanks guys.
I would not leave a defective servo connected to the CCU, a shorted motor can kill the CCU driver outputs. A better solution would be to disconnect the servo, but be sure that the servo is placed in the desired position first. (hot or cold)
Cheers,
Tore

pp000830

If anyone in the US has a used and non-functional servo available I would like to have it for a frankinservo attempt at a repair. If I develop a successful DIY solution I will share it with all.
PM me with your regular email address and a shipping address and I will email you a pre-paid USPS label to send it to me.
Thanks,
Andy
964 624 901 00 = Fresh air
964 624 902 00 = Defroster
993 572 905 00 = Temp mixing