Dodgy Dash is it the SI board or is it possessed!

[atw323]

Can any of you electrical wizzkids shed some light on my electrical issue.
I`ve only had the car a month ( a 90 325i cab) firstly the light dimmer blew and I traced the fault to a wire that was shoring against the ECU metal bracket. I`ve replaced the headlight switch it and it works fine now.
However after the dimmer blew I`ve been having trouble with the dash, the front and rear fog light warning lights glow all the time even when the lights are switched off, if I switch the fog lights on the tacho and the temp guage twitch, when I grive the car the temp guage rises up to red hot in 30 secs flat.
I`ve taken out the SI board which is the later lithium battery type and measured the voltage, they are both giving out 3v, so assume they are OK.
I did notice that when I stripped the dash down there was a cooper circuit board track on the dash part ( not the SI board) that seemed to be worn through and exposed, but not broken.
My other thought was a faulty earth, but i`ve measure the resistance and tighted the immaculate earthing point above the glovebox and they seem fine.
So is it the SI board, despite being the batteries being lithium and having voltage in them or it a polterguest possessing my dash!!!

All suggestions (or exorcisims) welcome.

Andy

[Brianmoooore]

Doesn't sound like SI board problems. The lithiums don't go short circuit and load things down anyway.
In spite of your checks, this does sound like an earthing problem.
Check the brown wires where they go into the cluster plugs and the soldering of the sockets to the PCB.
It would be a good idea to try a comlete fresh cluster in the car.
Where are you? Maybe someone on the zone near you has a spare one.

[atw323]

Many thanks for you pointers Brian, I`ll double check the earthing tonight.

I`m in Welwyn Garden, Herts if anyone has an old cluster I can just check against my possessed one?

Cheers
Andy

[atw323]

Sust it out, the shorting out of the headlight dimmer also caused one of the tracks on the dash clock PCB to burn out so the clocks were earahing through the fog lights warning bulbs causing them to glow all the time.
Once I`d soldered up the break the clocks worked fine.
However I think it has burned out my OBC as it lights up. but there is no display - oh well.

Thanks

Andrew

[martinclan]

I have a cluster from a LHD 325 (Speedo in KPH!) if you want to try it. I live in Mid Beds - about 30 minutes for you. I would like it back though...

Robin