MLHayes

I thought it was just low on Freon, bought the cans, and friend helped me install with a professional 3 hose, 2 gage rig. BUT the compressor will not come on, and will not draw the new Freon in. He forced the compressor on with 12v to the compressor clutch wire . we got the system charged and it blew cold air. BUT only with the 12v jumper. the dash ac button has no effect, and does not illuminate. w/o the jumper, just hot air, no compressor.

problem could be PCM ($$$$) or bad dash switch .

Does anyone have good schematics to show pin outs on the 12 pin connector on the back of the heater/ac control?

2010 JK

Mike

zstairlessone

A few things will keep a compressor from working. Over charged, high outlet pressure, no charge, high temp, blown fuse etc. if you jump the clutch, hook up high and low pressure gauges to see what the system is doing.

Sorry, no schematics for the electrical end. CAN bus controls it though.

MLHayes

after we got the compressor going with the hard jump, the system took the new Freon fine and the pressure gauges showed normal readings. nice cold air coming out of the dash.

I opened the control unit, (switch assembly) last night, not what I expected...... you really cant work on this stuff w/o schematics and a test bed, guess thats what they want.

toggle switch and duct tape could fix this ! LOL

mike

CharlesS

Look on the refrigerant filter drier (large cylinder near fire wall) and there will be a Low Pressure Cutout (safety) switch screwed into the drier. Remove the electrical connector and measure resistance across both leads. There should be continuity when the system has pressure. If there isn't continuity across the wires and you know the system has the proper charge; the LPCO switch is your problem and needs to be replaced...Otherwise.... the most common problem is the climate control modular circuit board.

MLHayes

Thanks Charles, I'll check that LPCO switch, makes sense

MLHayes

If I jumper across the leads, and the compressor runs, I will know its the LPCO

CharlesS

This does not confirm the problem is with the LPCO; it only confirms that the LPCO is holding the compressor clutch from engaging. Whether it is the system being low on pressure or the LPCO being bad must be determined by further troubleshooting. Read across the terminals on the LPCO and verify continuity across; if there is NO continuity and you know the system has enough refrigerant pressure to close the LPCO; then the LPCO is probably bad.

MLHayes

roger that, just a process of elimination,
HOWEVER, I came home, looked, and please help, WHERE IS the LPCO ....... looked and looked, cannot find the dryer cylinder, ....... must be $^*%#@ blind !

CharlesS

Sorry for the bad description.... The location I provided for the drier was on my '98 XJ and not your '10 JK. Your drier is near the radiator and condenser and the switch is near the firewall. Check the link enclosed and the switch is #15 and the drier is #22.

DesertdogBill

Recently acquired 2010 Wrangler 2 dr Sport, which I am told is a JK. AC was on when we purchased 10 days ago, and not turned off since. Then two days ago, my windshield was fogged up in the AM so I turned the knob from general direction into cab to defrost and turned output control from AC to off then slight heat.
When windshield cleared I turn fan down then off. Shortly later I turned AC back on and direction back into cabin and the fan back on.
NO AC... and have not been able to get to return since. I have tried all combinations including the additional button for recirculate, etc. Any suggestions greatly appreciated. Had the pleasure of a 93 Wrangler for several years around the millennia.