[z4] auto a/c turns itself off?

[thekurgan]

I had this also posted at Bimmerfest, but I think that board isn't as active as this board, so hope folks don't mind the cross post.

Has anyone had their a/c set to auto and then have the auto mode turn itself off? I have noticed it twice since owning the car. Neither day was the outside temp showing over 92 and I had it set at 74 usually, had some stop-and-go traffic and once I got going up to speed again, I looked down to turn it down lower and auto was off. I hit the auto button again and several miles later, it was off again. I turned the entire system off and back on again, set the temp, set the fan and hit "auto" but I was too close to home to see if it would turn itself back off.

Thanks for any info. I'm not going to have the dealer look at it if it's just some kind of hiccup.

[rsutoratosu]

I love cold air, I have my all the way down to left, like 64 but never on auto, manually set it on low.. maybe auto does turn off ?

[inTgr8r]

Originally Posted by thekurgan

Has anyone had their a/c set to auto and then have the auto mode turn itself off? .......

I'm sure there are system faults that will kick it out. Not sure what though.

Auto should stay on unless you make a manual adjustment.
e.g. if you adjust the fan speed, auto will kick off.

[thekurgan]

I didn't pull any codes, I at first thought it was the infamous outside temp gauge, but it was accurate to +/- 3 degrees. I personally think the sensor is too close to the ground, but that doesn't appear to be the cause. I believe rpm over 6500 shuts it down (the compressor), but I was just cruising to an offramp... weird.

[santov]

Could be a flapper motor that is trying to change the airflow (from floor to face for example).

It happened to me on several occasions over two weeks. When I took it to the dealer the couldn't replicate it (asshats were looking for the AC to turn off, not the Auto mode to turn off).

Hasn't been back for me.

[thekurgan]

Originally Posted by santov

Could be a flapper motor that is trying to change the airflow (from floor to face for example).

It happened to me on several occasions over two weeks. When I took it to the dealer the couldn't replicate it (asshats were looking for the AC to turn off, not the Auto mode to turn off).

Hasn't been back for me.

Thanks for the tip, I'll switch between floor/windshield/face a few times and see if I hear any noises.

[thekurgan]

I finally pulled a code for this: 2F99 ... "External Temperature Sensor Plausibility" ... seems the system has an issue with the outside temp sensor, which is in a shitty location. If I continue to pull this, I'll get the sensor replaced.

[CFoote]

Originally Posted by thekurgan

I finally pulled a code for this: 2F99 ... "External Temperature Sensor Plausibility" ... seems the system has an issue with the outside temp sensor, which is in a shitty location. If I continue to pull this, I'll get the sensor replaced.

Keep us updated, I'll be curious if a new outside sensor fixes it...