560 AC works intermittently

1987 MERCEDES BENZ 560SL
143,000 MILES • 5.6L • V8 • 2WD • AUTOMATIC
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LYSTGL
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Start the car, AC works great. Original R12 still ice cold. Drive to where you're going, turn the car off, come back, and AC no longer runs. No blower, no compressor. Nada. Can be on min or max, nothing works. Go home, start following morning and everything fine again until you shut the engine off.
Jun 30, 2019 at 9:38 PM
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STRAILER
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Yep, common when the control head goes out in these cars. here is a diagrams to show you how to replace it. Check out the diagrams (below). Please let us know what you find. We are interested to see what it is.
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Jul 2, 2019 at 3:43 PM
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LYSTGL
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Another wrinkle I discovered the other day. Took to taking a towel along and when shutting off the vehicle, I put the towel over the in cabin temp sensor and, lo and behold, when I come back to it and start it up, the AC and blower run! Keeping the sun off the sensor seems to work. Looking high and low for a 12383005721 in car temperature sensor now but having no luck at all. No one seems to have these anymore. I may be totally wrong but I suspect one of these is less expensive than a climate control module so am hoping I can find one and that it's the problem instead of the module.
Jul 2, 2019 at 4:17 PM
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STRAILER
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If the sensor shorts out it can cause this issue as well, finding the parts will be the issue, let me know what happens.
Jul 3, 2019 at 10:16 AM
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LYSTGL
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Will do!
Jul 3, 2019 at 10:18 AM
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LYSTGL
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Found a Mercedes dealership in Calgary Canada that has five of them still in stock.
Price is $89.00 Canadian or about $68.00 US. Downtown Mercedes (Scott) 403 232 6402.
Jul 3, 2019 at 11:08 AM
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STRAILER
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Good find :) let see if that fixes it which it should. Let me know.
Jul 3, 2019 at 1:12 PM