Questions and Answers
Jeep Cherokee A/C Not Working
Q. I have a 1990 Jeep Cherokee 4.0 liter, automatic transmission, P/S and A/C. The A/C clutch is not engaging and none of the service manuals I have show a fuse location or a breaker location. I only have a few breakers in the engine compartment and none of which are labeled. I thought maybe you could have an idea on how to troubleshoot the problem.
A. The first thing i would do is unplug the A/C Low Pressure Switch and jump the connections. If the compressor clutch kicks in, you have insufficient refrigerant in the system. If that is the case you will need to find the leak, repair it and have the system recharged.
If it doesn't come on, check for power at the light green wire of the A/C Low Pressure Switch connector. If there is no power, the problem is with either the A/C Mode Select Switch or the wiring between the A/C Mode Select Switch and the A/C Low Pressure Switch connector.
Here is the A/C Clutch relay: