I have been trying to diagnose my 2005 E320's AC system. Car has the two-zone 580 system. It started last summer, actually. Randomly, the AC would go warm. This year it got worse. Goes warm or cold on hitting bump. When not working, it feels like the compressor is not working-both high and low-pressure lines are same temp. This happens whether car is warmed up or not, so it can't be a hot water valve problem. System is permanently warm now. I have had a friend run diagnostics on it and he came back with some inconsistent actuator failures, but all vents go warm at the same time and compressor cuts out. The charge seems normal-we were measuring 100psi last night on the low pressure side with ambient temp close to 100 degrees. No change occurred with engine running, AC on or off. The diagnostics falsely reported 10 bar pressure (low side I think), so we may have a bad pressure sensor under the hood. I cannot find any diagrams that show the actual wiring of the refrigerant temp/pressure sensor and the compressor. These connect to the driver-side SAM. Resistance measurements and wiring diagrams would really help. I found nothing on these areas in WIS. Please help.