Had an interesting weekend. Saturday, the "new" '92 745 had a blown MCC/Air Conditioner fuse (#16 - 30A). Replaced the fuse, and all was well. Didn't worry too much about it. Then, after about 5 minutes of AC (perfect cooling), the compressor kicked off, but all of the other HVAC stuff worked. Odd.

I discovered that, after allowing the car to cool/rest, the compressor would kick on just fine, and was cooling perfectly, but then would kick off after about 2 minutes. I watched the compressor as, first, the clutch began to slip, then the unit would stop completely, indicating a gradual loss of electricity. I jumped the terminals at the low pressure switch. The engine computer raised the idle as normal, but the compressor didn't come on. So the low pressure switch was fine.

Then, I read the FAQ and resoldered the control unit as specified, even though the unit was replaced with a brand new one ($487!) by the previous owner just a couple of months ago, before I bought the car. I'm thinking the replacement was done because of this problem, and they paid for the wrong thing.

The next thing I'm going to check is the wires/ground at the compressor, probably this evening. Any other suggestions? The problem appears to be heat-related, similar to a fuel pump relay in need of soldering.

Thanks in advance.
--
Guid ('88 244DL 213k, '89 744T 167k, '92 745 163k)