BMW Repair: 325 Electrical Problem, loose ground, intermittent operation

Question
Greetings:
I have a 1994 BMW 325 with an electrical fault. The entire instrument panel works intermittently...when driving, the entire panel will go dead...no lights or any analog displays. Usually after driving a few minutes it will come back on again. I have pulled the panel and checkedand cleaned the connectors to no avail. Do you think this could be a ground fault? If so,  what grounds would you recommend checking/cleaning?

Thanks,
Jim

Answer
Jim, I don't deal with E34 very often/ever, but any intermittent operation can be cause of faulty Power or Ground supply. Keep in mind that very few Control module have it's own ground that isn't shared by other units. If it were a loose ground I would expect other Control units or systems that share the same ground would be effected. Having said that let me contradict myself by saying that it is possible and worth while to check. Connector X17 has two grounds for the instrument cluster Pin 1 and 13. Should be brown color 24Pin connector. All BMW ground wires that I have ever dealt with are solid Brown in color. I believe the Ground wires off the Cluster are Brown with orange tracer stripe. Ground connection 1160 should be in the driver's footwell. Hope this helps
-Evan