I already did a search and come up with some info. Since I do not have AC pressure gauges to check for low r134 (it was converted about two years ago) I jumped the low pressure switch (s31/1) and the compressor still does not engage. That leads me to believe it is NOT low refrigerant pressure preventing the compressor to engage. I also already checked for belt slipping or loose (it is NOT).
The problem, according to my son (he drives this car now), started after I replaced a bad fuel pump relay. So I suspect, I somehow, messed up the klima relay since it is in the inmediate area.
I am troubleshoting the compressor cutoff procedure in the automatic climate control manual, specifically job 83-605, and my question is this: Does the vehicle has to be on (running) through the whole procedure or just the key in the on position (car NOT running)?
Any other suggestions? or tips?

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J.H.
'86 300E