HELP! Half the intstrument cluster wont work!

[Biggy786]

Hi all,

Im wondering if you can help me.. i have a 89F 325I Sport

Everything was fine until suddenly one morning i lost my rev meter/mpg calculator and temp gauge. Needles dont move!

my MPH and fuel gauge still work as normal?

any ideas on rectifying this somewhat peculiar problem?

Many thanks in advance!

[Felix79]

ok the rev counter controls the mpg guage. Normally the temp guage will be a small bolt doing the contact on the back has come lose.

It's really really easy to change the parts of the cluser or put a new SI board in. Search the techincal area and you will find loads for this. Any probs I am happy to talk you through step by step how to remove your cluster and what to look for. If need be I can sell you a spare rev counter

[ImysE30]

Most likely the fuse will be blown, check the fuse box first

[daimlerman]

The circuit board for the servive indicator has two ni-cad or lithuim batteries.
These will have failed and will need replacing.
What's the SI got to do with rev counter,MPG meter and temp gauge?
All of these instruments imput into the SI board,so a failure on this board stops them working.

[m_jermyn]

Malcom, mate I have removed the batteries from my cluster completely and everything works fine. Except the service lights.. Now I dont believe anymore that the nicads cause any dramas in the cluster at all. The temp gauge problems I had before were diagnosed as the batteries so I was in the middle of changing them when I had to go to a emergency job, so i just screwed the cluster back in and shoved it back in the dash without the batteries. Believe it or not it all works fine.

I have a small wiring issue as sometimes needles jump around but if I move the cluster a little it all stops.

I think he has a wiring issue.

Mike

[Biggy786]

thanks alot guys you have been great help, this will keep me busy on the weekend

Felix if i have no joy il give you a shout with that next cluster mate

thanks again.

[Brianmoooore]

Now I dont believe anymore that the nicads cause any dramas in the cluster at all.

When the NiCd batteries fail, they go short circuit and heavily load the power supply rail to the rest of the circuitry. Removing the batteries will obviously remove the short!

[m_jermyn]

Thanks Brian that explains it then.