996 Climate Control Gremlins?

[burton161]

I recently purchased a 2001 996, and while I'm very much enjoying the ownership, the climate control seems to have a mind of its own. I can set it to a desired temperature/fan speed etc., or use the Auto function, but every time I start the car, the climate control seems to switch on in a different mode - e.g. Sometimes the aircon is on, sometimes it is off, or the Auto function is activated. The temperature setting never seems to be affected though.

Has anyone else experienced this, or is it a special 'feature' on mine only?

Any advice or shared experiences would be appreciated.

Thanks.

[Zoin]

Never noticed any such issue on mine (2002 996) so it would appear to be a 'special feature' on your car.

Very annoying, I should imagine. Best of luck getting it sorted.

[Rockster]

burton161 said:

I recently purchased a 2001 996, and while I'm very much enjoying the ownership, the climate control seems to have a mind of its own. I can set it to a desired temperature/fan speed etc., or use the Auto function, but every time I start the car, the climate control seems to switch on in a different mode - e.g. Sometimes the aircon is on, sometimes it is off, or the Auto function is activated. The temperature setting never seems to be affected though.

Has anyone else experienced this, or is it a special 'feature' on mine only?

Any advice or shared experiences would be appreciated.

Thanks.

If the system is left activated when the engine is shut off and the engine is then restarted at a some other time and the outside temperature is below a certain temperature (34F?) the A/C compressor will not be engaged to avoid ice developing on the evaporator.

This is the only case I am aware of in which the system comes on in a "different" mode or state from one in which is was in when the engine was shut off.

If this is not what is happening then all I can offer is the only time I have observed inexplicable behavior from my 03 996 Turbo -- the car's radio system -- is when there was a failing battery.

The radio would come on when it was off before when I shut off the engine. It would come on but not work. That is all buttons would function except I could not hear anything. It would also switch from AM to FM or switch to an invalid station frequency. The only way to "cure" this condition was to shut off the engine and wait for 5 minutes for the car's electrical system to fully power down. (Or I could turn off the engine and remove the related fuses but this was a real pain.)

Might add that I suspected a going bad ignition switch but the battery finally failed outright -- thankfully before I had a new switch installed -- and after installing a new battery the radio problem went away and have not reappeared.

I hardly ever shut off the engine with the A/C on (in auto mode). Almost always I shut off the A/C compressor a few miles from my final destination and let the fan continue to blow air to dry the car's A/C system to avoid the build up of mold and mildew.

Perhaps if I had left the A/C in auto mode and restarted the engine with a failing battery I would have observed the same thing as you?

[burton161]

Thanks for your comments.

There doesn't seem to be any pattern to the behavior of mine, so it's very hard to narrow down what conditions might be causing it. I may have to resign myself to the fact my car has this 'special feature', until I can pin down the pattern.