[Jemellh]

Is it possible for your cars ac to work with the ambient sensor reading -40? I bought the car in May. Replaced the condensor and compressor. The car was in a accident in the past and the idiots ripped out the wiring for the ambient sensor. somebody told me the ac can work fine without the ambient sensor but im not sure how true that is.

 

[l1tech]

The only way the ac could work with without the ambient sensor is if it were coded out and I'm not sure that that is a possibility. The wiring for the ambient sensor just didn't disappear, it's there somewhere, you might have to go into the wiring harness to find it though.

 

[Jemellh]

Where is the wiring harness? Under the hood

 

[l1tech]

On your particular vehicle you would have to find out where the sensor is supposed to be mounted originally and then look for the closest wiring harness to that location. More than likely the wires are poking out of the harness as I doubt anyone opened up the harness to cut the wires further back.

 

[toga94m]

So, nothing in your other thread was helpful? http://www.bimmerfest.com/forums/showthread.php?t=919546&highlight=

AC control will use the intake air temperature from the engine as a substitute, if the real ambient sensor is defective.

If a fault is entered, a substitute value is calculated for the ambient temperature from the intake-air temperature. The ambient temperature is required for many functions in the engine control module that contain temperature-dependent parameters.