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Discussion Starter #1
OK here is what I have, no power to the GRN-BLK wire to power the compressor. With gauges I have Freon, at rest 70 psi high and low side same (compressor not on). It was cooling OK after I put in one can of Freon a few weeks ago. I went in and swapped out the compressor clutch relay behind the dash, no change. I can hot wire 12V to the compressor and it kicks on and begins to cool and then the rad fan kicks on as it should. I also disconnected and reconnected both large round connectors behind the false firewall. Jumpered at the three way switch and that does not turn on the compressor or the rad fan from either connector. I of course checked the fuse for the A/C as well. Do I have a bad temp control panel? This issue just started yesterday. No trouble codes from the temp control panel either running the self diagnostic. Any help would be appreciated.
Charles
 

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With key on jumpering brown and black wires in white connector at trinary switch on A/c black receiver dryer cylinder should turn on radiator cooling fan.

With key on ground gray-black wire in red connector at receiver dryer to ground and cpmpressor should engage if so the maybe switch in a/c panel bad. If that doesn't work go to frost switch under rectangle cover near expansion valve and ground gray-black wire and see if compressor engages.

It could be bad switch in a/c panel but first verify frost switch is good
 

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Discussion Starter #3
Thank you so much for that info Steve. I got the fan to run from the trinary switch jump but couldn't get the compressor to run with the grey blk grounded at the trinary switch, so moved on to the frost switch. That grey-blk grounded did not run the compressor either, BUT when I plugged it back in to the frost switch, it came to life! Seems to work fine now, shutting it off and on at the control panel. I guess it was just a dodgy connection there. Maybe I should get a new one anyway. Thanks again! My family is moving into a new house this coming week and I needed to get this resolved, so truly grateful for the help. :D
Charles
 

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I don't think this thing is ever going to frost up with an R134a retrofit. Maybe I should just move the frost switch connectors to the two upper tabs to bypass this thing permanently? What do you think?
Charles
 

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I don't think this thing is ever going to frost up with an R134a retrofit. Maybe I should just move the frost switch connectors to the two upper tabs to bypass this thing permanently? What do you think?
Charles
I think if you do that the compressor may stay on all the time. It seems like my friend Lee did that by mistake and had a problem. I can't remember exactly what happened.
 
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