Faulty Rev counter in '86 320i

[heraldohiggens]

Hello

Ive a '86 320 with rev counter/temp gauge not working. Stuck a working cluster from a 1990 320 in putting the 86 coding plug into the 1990 cluster.
The temp gauge now working but not rev counter. Also when plugging the cluster back into the '86 car I can only seem to find two plugs to fit back into the cluster even though in can accomadate three, the one for the middle seems to have been swallowed up by the car.

Can anybody advise?

thanks

[Brianmoooore]

First of all, welcombe, on behalf of the management, to the zone , the world's biggest repositry of E30 related knowledge.
First of all, the yellow socket is for an OBC, so if you don't have one, then don't worry about the yellow socket.
For your revcounter problem, a common cause of this is a poor connection on the black wire (pin 9) of the C101 engine loom plug and socket (the big plug and socket on the bulkhead, just inboard of the fusebox).
Another possibility I suppose is a dud coding plug, but I've never heard of a dud one before.

[oze30]

I got exactly the same prob.

How to fix the wire in the plug? I think the previous tried that.. hence the black wire in my engine bay.. but it doesn't work. If I turn my car off.. the revs sometimes jump a bit.

[oze30]

bump


whats the green plug with one blue wire for?

[Brianmoooore]

bump


whats the green plug with one blue wire for?

Gtrrn plug mainly has road speed outputs. Used for cruise control (I think). and for speed contolled radio volume. Blue wire probably goes to the radio.

On the rev counter not working, sounds like someone's already tried and failed, so the usual solutions probably won't work.
A dedicated output from the ECU feeds directly to the instrument cluster, so try replacing one, then the other.

[HartgeH27]

Nice one Brian..........yet again excellent service !!!

[oze30]

the 101 plug is the big round plug on the firewall??

There is no wire in No 9 spot on the female. Just the male. The black wire I think was for the anti theft??

[Brianmoooore]

the 101 plug is the big round plug on the firewall??

There is no wire in No 9 spot on the female. Just the male. The black wire I think was for the anti theft??

C101 is the big plug on the bulkhead, yes.
Both male and female halves should have a black wire in position 9, feeding engine speed information from the ECU to the instrument cluster, according to every E30 loom I've seen and every wiring diagram I've used.

[oze30]

so what does it mean if there's nothing in the female pin 9?

[Brianmoooore]

so what does it mean if there's nothing in the female pin 9?

Someones been messing? Is this the car with the seperate black wire fitted?