Short version: Currently radio and gauge cluster turn off very briefly going over bumps.
Long Version:
Been having this problem on and off for quite some time. Thought it was the battery cables as they are a known fail point. Replaced them with 1AWG cable. That solved the problem for awhile. Then on an off-road trip this fall my car just died on trail. Got a tow back to the shop, replaced the CPS as my fuel gauge and voltmeter stopped working and that seemed like the logical culprit. No dice there so I took it to a mechanic friend, first thing he did was check all the fuses (this will be important later) then we replaced the following: PCM (twice), ASD relay and fuel pump relay. My mechanic also cleaned all grounds and unwrapped and went through pretty much the whole engine harness. Eventually we found what I think was the original culprit. Got under the car and the connector for the reverse lamp switch had fallen onto the exhaust and melted through. At this point my mechanic (who was now on a mission!) went through the fuse panel again and found a blown fuse for the reverse lamp switch. So once we replaced that fuse the car started. So what I think happened is the connector melted and shorted out which blew the ASD relay instead of the fuse on that circuit (weird?) then when we replaced the relay it blew the fuse like it should have originally and once we replaced that fuse it fired up. Then for E36 M3s and giggles we swapped back in the original PCM and the first replacement PCM and both worked fine. So probably the ASD relay was what was actually bad. Or maybe the CPS.
So fast forward to today and I had a buddy get in the car while it was running and wiggled every wire I could, in hopes of causing the radio/gauges to turn off. Nada. We also cleaned all the grounds as part of the diagnosis portion of my previous electrical problem so those are still all sparkly and tight.
With that I turn to you, Grassroots gurus. Whatcha got? Oh also the HVAC panel is completely dead.
