rev counter not working

[tommy22]

can anyone help my rev counter has stopped working

[Zayyan]

Hi Tommy, welcome to the Zone.

I put a thread up about this a few weeks ago and the first suggestion fixed it, I think I owe Brian Moore a pint actually

Gimme a sec and I'll find the link

[Zayyan]

Here you go:

http://www.e30zone.co.uk/modules.php?na ... ic&t=24639

Good luck with it

[Brianmoooore]

Hi Tommy, welcome to the Zone.

I put a thread up about this a few weeks ago and the first suggestion fixed it, I think I owe Brian Moore a pint actually

Gimme a sec and I'll find the link

Or I could post it again. Try unplugging and plugging together the big C101 plug and socket on the bulkhead next to the fuse box. Pin 9 carries the tacho signal.

[tommy22]

thanks will try that when i got some light.
will let you know how i get on.

[massive]

Worst case senario you might have to get a replacement cluster. Ԛ£15-Ԛ£20 off here.

[tommy22]

have cleaned the ecu plug and the c101 plug still not working and tryed a new set of clocks

[Brianmoooore]

There are more than one fuse associated with the instruments. Not sure off hand what the effects of individual blown ones are, but check fuses 10 and 12.

[tommy22]

fuses ok someone said it might be that wire that comes off one of the ht leads

[eun]

welcome mate

i have the same problem just havent got round to sorting it yet.

it happened after i put the 2.5 in from the 1.6

my mate steve dropped a 2.5 in his 320 and his has exactly
the same problem.

brian u know your stuff....can u tell me what it could be?

anything to do with the engine?

cheers

[Brianmoooore]

fuses ok someone said it might be that wire that comes off one of the ht leads

Nothng to do with that. The tacho is driven from pin 6 of the engine ECU, along a black wire to pin A7 of the instrument cluster, via pin 9 of the c101 connector, so, if you've changed the cluster, and all the cluster supplies are OK, then there's not a lot to be wrong.

[gcorky]

There are more than one fuse associated with the instruments. Not sure off hand what the effects of individual blown ones are, but check fuses 10 and 12.

fuse 21????

[Brianmoooore]

Yes, you're right. Thought there were three fuses associated with the instruments, but fuse 21's not mentioned in the handbook as being anything to do with them.
Looking at the wiring diagrams though, fuse 21 provides "memory power" to the SI / tacho drive board.

[tommy22]

Tryed fuse 21 it was ok.
Does anyone else know any more about it

[Brianmoooore]

Does anyone else know any more about it

That's all there is - three supplies to the cluster, not all of which are associated with the tacho, and a single wire from ECU to the cluster.
Time to recheck what you've already checked.