The A/C compressor has an intermittent issue, it will drop out of operation for days at a time, and then I will run over rough road or a RR crossing, and the compressor will start operating again! Anyone else had this issue, and if so, any idea of where a loose connection might be? Fusing issue? Thank you!

 

Relay #8 in the FRONT POWER DIST BOX is the compressor clutch relay. Pull the relay and jump the pins #3 and #5 to power the compressor clutch. If the clutch engages then a low voltage or poor connection (faulty relay?) might be causing your faults. If the compressor is not responding, try tapping the clutch plate on the compressor with some sort of stick to help engagement to see if the clutch plate distance is too great or the magnetic coil is weak/faulty and needs replacement. There are shims on the compressor shaft to set the clutch plate gap, so adjusting it might be required!!

bob gauff

 

Bob - OK, your troubleshooting was perfect, the clutch engages when shorting the 3-5 terminals, but apparently the relay isn't receiving any voltage to pull it closed - I switch with another relay of the same part #, and got no engagement. Can you please walk me through the next step from the power box terminals back to the control? Thanks, Ted

 

Question - if I were to jumper the terminals #3-#5, would this keep the compressor running continuously, not taking any inputs into consideration from evaporator defrost, low pressure switch, etc.?

 

Yes and the battrey would die unless you unplugged the wire.
Pin #1 is the power wire for the relay coil. It has a Fuse (#11--15Amp).
The earth for the relay coil is the ECM so There might be a fault logged in it or the Climate Control Module. You need to scan the entire car, it will be faster than checking every fuse,relay,wire etc.

bob gauff