[W126 Coupe] Suspect OVP relay (old subject-sorry)

[Vance Rowley]

I know this subject has been covered many times, but there doesn't seem to have ever been any exact diagnoses, and appears to be some confusion on the subject.
The symptoms are as follows on my 1991 560 SEC (Euro).

1. Takes a long time to start, (where it used to start on the first couple of turns of the engine.)
2. High idle, around 1400-1600 rpm (and sometimes creeps up).
3. ABS and ASR warning lights on all the time.
4. Hesitate slightly when you hit the gas. (more noticable when you rev the engine in neutral)

This I believe is the typical (limp home) mode. I have seen these symptoms on many forums as well as our archives, but never usually all at the same time. Also, these symptoms that other people have are usually intermittent, where mine are permanent. Anyhow, there are quite a few different diagnoses for these symptoms around on the net, but mostly point towards the overvoltage protection relay. I have of course checked the fuse in the top of the relay and is OK, as well as making sure the pins are clean, which of course they are. Have even tried one tip to disconnect the battery overnight to try to reset the system. No joy.

My main question (before I purchase a new OVP relay) is, can anyone confirm that this is the problem for sure. Also, I unplugged the relay and started the car and all the above symptoms remain the same without the relay even plugged in. This got me thinking. Does this mean if you unplug the OVP relay on a known good working car, that you will get all the above symptoms? This would surely confirm the diagnoses and was wondering if anyone has done it. If so, please let me know, as well as any other tips or hints.

Thanks,

Vance.
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