speedo problem

[Kid_318i]

I have an 84 318i and when I bought the car the speedo workout fine, I changed the instrument cluster because the fuel gauge wasnt working, but the speedo still work. Then later in a trip the speedo stop working, and started to work again and now it doesnt do nothing. I have to instrument panels and both speedos doesnt work. I changed the sensor in the diff, I changed fuses, replace SI batteries because they were bad, changed the instrument panels, I soldered the back of the speedo and still nothing jejejeje, can somebody help me please, thank you.

[wayne003]

Hi kid_318i

I have a 320i e36 and had a similar prob, both my speedo and fuel gauge not working.
I ripped out the dash passenger seat and carpet it took me weeks to find the problem, it was so simple

the fuel pump and speed sensor in the diff have the same earth wire, I couldn't find were it was bad so cut it close to fire wall on left hand side of car and gave it a good know earth it now works fine.

hope this helps you out go bimmers

wayne

[Kid_318i]

Hey thanks good observation, I'll check it out.