MyLittlePony
Active Member
I have a convertible. I rarely use the AC. A while back, I discovered that when I do use the AC, the engine overheats. No CEL though. This problem has since been corrected, and now blows ice cold with no overheating. HOWEVER, it now will randomly turn the CEL on, only to extinguish itself a few seconds later. Car behaves normally though.
When I run the codes, AC off, I get:
511 511 172 628 172 628
AC on:
511 539 511 539 1 172 628 172 628
511 - EEC Processor Read Only Memory (ROM) test failure
Car has a chip
172 - o2 Sensor circuit indicates system lean (right side)
Both O2 sensors have been replaced, and still has this code
628 - Converter clutch Lock-Up error
Car has a shift kit on it.
539 - System shows voltage at PCM pin 10 Is A/C on ?
Yes.
Basically all of these codes have existed within the system for years, and never once have thrown a CEL. One would think that whatever is now setting it off would be enough for the code to be stored somewhere, right? And it only turns on when the AC is running. A new compressor and drier were installed, but I can’t see how an AC system would throw a code, and if so, what?
When I run the codes, AC off, I get:
511 511 172 628 172 628
AC on:
511 539 511 539 1 172 628 172 628
511 - EEC Processor Read Only Memory (ROM) test failure
Car has a chip
172 - o2 Sensor circuit indicates system lean (right side)
Both O2 sensors have been replaced, and still has this code
628 - Converter clutch Lock-Up error
Car has a shift kit on it.
539 - System shows voltage at PCM pin 10 Is A/C on ?
Yes.
Basically all of these codes have existed within the system for years, and never once have thrown a CEL. One would think that whatever is now setting it off would be enough for the code to be stored somewhere, right? And it only turns on when the AC is running. A new compressor and drier were installed, but I can’t see how an AC system would throw a code, and if so, what?
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