Jump to content

Compressor won't start

Recommended Posts

Hi Jonny,

I had a system installed on my 1991 964 few months back.

I have a batter isolator installed at the negative side of the battery.

It was running fine till car was on the jack and battery was disconnected for few days.

Firstly the compressor was running intermittently for short period of time and not running at all.

.Doesn't responding the CCU switch nor the PUTTY command line CMP=50 or CMP=100

I have deleted the contractor as per service bulletin.

Also I did check the 3 separate voltage from ECU side connector. Trigger did responding to the CMP=50 or 100 and reading 6.15V or 12.8V.

I have attached a picture of the status from PUTTY. 

I can see the compressor current is reading zero but the compressor speed is showing 090. 

Any idea what will my cause?











Screenshot 2023-03-27 at 10.12.56 PM.png

Link to comment
Share on other sites

Thanks Jonny,


Managed to bypass the battery kill switch, doesn't help the situation.

Also I connected the 12v to RED, ORAGNE and GREEN and ground to BLACK from the compressor connecter.

It didn't start the compressor neither.

Any advice?




Link to comment
Share on other sites

This topic is now closed to further replies.
  • Create New...