I found the forum when looking about my jeep not starting and with the information on this site found out my cps was at fault. I have a new problem with the 97 cherokee. The ac recently stopped working after I just recharged it. Now the compressor doesn't get power so i searched the forum and checked for power at the low and high side sensors and there was .3 volts power there. The fuse is not blown for the a/c clutch and the relay is good. I cleaned up the ac switch like the how to rebuild the neutral safety switch and still no power. Does anyone know what wire is the power from the pcm for the compressor or is there anything else I should check out to get my power back to the compressor?

 

Will the compressor or A/C work if you jumper the compressor power wire directly to the battery?

 

yes it works when i do the jumper wire

 

Thats good. Compressor & clutch OK.

Could still be the low presure switch not letting full power through to engage compressor.

If you jumper that switch, will compressor kick on?

 

no that won't make it work either. theres only .3 volts getting to the low pressure switch

 

nospeed01 I'm sending you a Private Message.

 

If you are not getting power to the clutch, are you getting power to the low pressure safety switch? It is located on the filter/drier on the passenger side frame rail. If you are getting power to it, you probably lost your charge after you filled it. Any signs of oil spots near your schrader valve?

 

He said earlier that he was getting only minimal voltage to the low pressure switch. It sounds like the trouble is further up the line.

He said jumpering the switch didn't help; compressor didn't come on.

 

last night I was messing with it and cut the compressor connector off of a jeep at the junkyard then ran a wire from the compressor to the lights on the ac switch and the compressor comes on and the ac now works when the lights are on. could the relay be testing ok but still be bad only be letting minimal voltage out?

 

Dude, go back to the safety switch I told you about. Don't run it until you do.

 

Please read the original post theres only .3 volts going to the switch thats the problem. if I've read right the power goes from the safety switches to the compressor and with no power getting to the switches the compressor doesn't turn on. I've already tested the safety switches, checked the fuse, tested the relay, and the compressor. I'm not sure on what wire on the ac switch turns on the compressor or which wire from the pcm

 

Yes I understand .3V In between the dash and your compressor is the safety switch. It is there for a reason. Check the voltage going in. I have lots of experience in AC repair. If you charged it, you cold have lost it for several reasons. If you did, your safety switch is trying to tell you something. If you have only .3V going into it then look elsewhere. This is only good troubleshooting technique, the same thing a good technician would do. But if you insist on trying to ruin a compressor, well it's your compressor.

 

Am I not being clear? I'm trying to look elsewhere but I don't know where to look and was hoping someone on the forum would know where to pick up where I left off or maybe theres a step I skipped . If theres low voltage going into the low pressure safety switch where is the power coming from to give that power? Which wire for the ac compressor comes out of the ecu? Which wire behind the ac switch controls giving power to the compressor?