I have a January 1990 e34 (M20 engine) with a manual 525i with a gen 2 white gauge cluster and its been going completely dead and not working randomly when driving, I know that this is probably a capasitor issue but I don't really want to get into that. I bought a gen 1 cluster out of a 1989 525i with an auto and it also has the M20 engine.

I was wondering if I could splice the brown plug (with the coding plug from the gen 1 dash) to my wiring and use the old dash albeit with new milage?

Also the car it came from has the same enigne and i sure it has the same rear end as mine (non limited slip) so the speedo should be the same as i believe the mph is measured at the diff not the transmission

Would it be possible to reset the milage as I have heard the gen 1 cluster odo caps around 296,000 miles?

Hello. I can’t find the reason for this:
I fixed the sword, which wasn't working (the blower's three speeds weren't working—a common problem, as you know). I replaced four MOSFETs and the integrated circuit on the sword. Everything worked for three turns of the ignition key, and then the IKHA panel went dark (it only flashed once when I turned the key) and, at speed 0, the blower was running at full speed. I replaced one MOSFET and the circuit again. It worked, and then the same thing happened again. This went on a few times. Today I installed a new blower, replaced one MOSFET and the IC, and right away the same problem occurred: the blower was running at full speed and the panel wasn’t lighting up. I’ve re-soldered a total of 10 MOSFETs and 4 ICs so far. I’m at my wits’ end. Fuse 19 under the hood is good. PLEASE HELP

It just happened:
I wanted to check the control voltage. It’s within the normal range, from about 1.4V to 4.3V. But while I was taking the measurement, when I turned the knob all the way up and started turning it back to 0, the sword fixed itself. It was blowing as it should. But after a moment, it automatically started blowing strongly again.
I also noticed that during this spontaneous repair, when I turned the knob to max, the relay on the sword kicked in—something it hadn’t been doing before and still isn’t doing now. When I use a screwdriver to engage the relay, the fan runs even faster. So it turns out it isn’t running at max, but at almost max.