OMP

Hi there. Car is a 200 10V Turbo automatic. MC1 engine.
Some years ago, electricales wetn crazy and some of the wiring had to be rebuilt.
All electrical functions where redone and work OK, EXCEPT for the A/C higher rpm when the A/C is in AUTO.

So, when using the A/C, at idle, voltmeter will go under 12 volts as rpmīs go lower ( no jump in rpm ). A/C will blow very cold air and all A/C funtions work.

So I really need to know where does the ISV controller is getting the signal so that ( based on some research) ISV controller sends an additional 3V to the Air valve rising rpms by a bit.

SJM website mentions that PINS 5 and 6 are the input ones getting a signal ( 12V I guess) from the A/C compressor directly. Is that right?
Would you know color of wiring getting there?
I have a couple of green wires on the engine bay cut not really knowing where they should go but could be these ( other possibilities would be an old fog light installation wiring or alarm).

So, anyone knows how if the signal to the ISV controller is a direct wire ( both ) to the ISV ( which one would ge where? Positive to pin5 or pin6 or negative to pin5 or pin 6?

Is that the correct "diagram". Other forum fellow wrote that this signal comes from the HEad Unit, but I still think it does come from the compressor itself.

Any help on this would be greatly apprciated.

Many thanks

audi_marv

I would also think the signal comes from the Head Unit. Probably from compressor, to head unit, to ISV. You may want to check the head unit pin functions just to check.

Another source may be the ISV control unit in the Aux fuse panel. Possible the ISV unit itself is the culprit.