I have a 1986 420 SEL, and am having some problems.

I had the a/c compressor replaced with an MB reman unit approx. 2wks ago.

My problem is this: the fuel, oil pressure, and temp gagues intermittently "die". There is no rhyme or reason as to under what conditions this occurs. All other instrument panel functions work OK. When this happens, the a/c compressor also kicks off, and no more cool air. These are the only systems that are affected by this.

When this first happened about a week and a half ago, I replaced the fuse for good measure and cleaned the contacts. (it is not blowing the fuse btw). The problem stopped. Yesterday, the gagues died and no a/c compressor.

Is there a relay somewhere that I need to check before breaking out my multimeter? I have looked in my electrical troubleshooting manual, and it only shows the fuse and sending units in the circuit.

I think that if it were the left bank of gagues, there would be other problems with the instrument cluster, as the wiring harness plugs into the back of these

This never happened before replacing the a/c compressor, so I that leads me to think that the problem is with the a/c compressor or some related relay.

Any help appreciated, thanks.

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