2000 C280 air conditioning
 

Hi All,

The a/c in my 2000 c280 (with digital climate control) has not worked for about three months now (it stopped working after the car was not used at all for two months). Finally I got myself to take some measurements. As the system does not have a high side port, I took the high side measurements from putting the climate control into diagnostic mode. All measurements were taken at a 90F ambient.
Static pressure: 107psi
Pressures at 900rpm: 98psi-low and 114 psi-high
Pressures at 2000rpm: 82psi-low and 131 psi-high

I find these values strange. To me they do not look as if the expansion valve was stuck in or out. Do these compressors have an internal pressure relief valve that tends to get stuck?

Any ideas?

Thanks,

Greg