Instrument Cluster

[Benleslie13]

Hello. I am new to the forum but have been using it for the past year. It has been very helpful.

My question is regarding an M5 cluster that was installed in a 1986 E28 535i. The engine is from an E34 (M30B35). I don't know anything about the donor cars for the cluster or engine. I bought the car last year. The car runs great, but I am a little afraid to take it too far or fast due to the instrument issues.
All the warning lights work (ABS, Brake, Battery etc.) The "Check" light works. Fuel gauge works.
My indicator arrows don't light up (the lights themselves work), the temp gauge does not seem to register anything (always on cold), the tac doesn't go above 3000, and the speedo doesn't go above 40.
I am not even sure where to begin. I don't really want to take the cluster out until I have at least some idea of what I am looking for. Do the terminals just need to be cleaned? Are the batteries leaking? Or is it more of a compatibility issue?

Thanks
Any direction will be helpful.

Ben

[Aldo525]

Hello. I am new to the forum but have been using it for the past year. It has been very helpful.

My question is regarding an M5 cluster that was installed in a 1986 E28 535i. The engine is from an E34 (M30B35). I don't know anything about the donor cars for the cluster or engine. I bought the car last year. The car runs great, but I am a little afraid to take it too far or fast due to the instrument issues.
All the warning lights work (ABS, Brake, Battery etc.) The "Check" light works. Fuel gauge works.
My indicator arrows don't light up (the lights themselves work), the temp gauge does not seem to register anything (always on cold), the tac doesn't go above 3000, and the speedo doesn't go above 40.
I am not even sure where to begin. I don't really want to take the cluster out until I have at least some idea of what I am looking for. Do the terminals just need to be cleaned? Are the batteries leaking? Or is it more of a compatibility issue?

Thanks
Any direction will be helpful.

Ben

Hello, in my opinion, your cluster batteries died or not charging as the new ones.....typical symptoms are as you describe, erratic tacho, no temp gauge, etc.....but the indicator lights not working could be bad bulbs (the two of them??...rare) or a bad connection on all central cluster area....that central part use two small screws to be attached to the main circuit plate. And of course, maybe some bad connection (rust??) on the main cluster connectors (White, Blue and Yellow)

Does the service lights work???....inspection, oil service????

Any of these repairs or checks needs the cluster to be removed an opened.

Re the compatibility, maybe (but I'm not an expert) the tacho could not be accurate if the coding plug is not compatible between a normal 535i and M5.