e30 s52 swap tach mpg temp gauge not working

[drken]

I had read that the C104 is on later models.

No, I think the c104 is in the earlier models. I have an 87, and it was behind the glovebox. NOTE: When I Pulled my OBC and other interior wires (for race car strip) I temporarily lost those functions. I found that there was a spare, unused wire zip-tied ( I believe by the factory) up under the dash. It plugged right in to the c104, and functions returned. I think the factory just plugged one connector in if you had an OBC, and another connector if you didn't.

Good Luck!

Ken

[duval7]

Did you have a pin 8 and 9 on your body side E30 c101? If so, then you are wired through the C101. If not, its through the C104.

I just checked, and pins 8 and 9 are wired in the C101 plug. 8 is a YL/WHT wire and 9 is a BLK wire. What do i need to do with those two?

[NickL]

Are there pins wired to those? Should be a black wire to the black wire, and a white/black wire to the other. Colors could be different though.

Pin 8 to pin 24 of X20
Pin 9 to pin 20 of X20

[duval7]

Are there pins wired to those? Should be a black wire to the black wire, and a white/black wire to the other. Colors could be different though.

Pin 8 to pin 24 of X20
Pin 9 to pin 20 of X20

Yes its just like you said a black wire at pin 20 and a wht/blk wire at pin 24, but even with those hooked up to pin 8 and 9 of the C101 the tach still doesnt work. Everything else on the cluster works. I notices from the ETM that C1 pin 7 on the back of the cluster is the input for the engine speed. Should i try and run a wire from pin 9 on the X20 straight to the wire at C1 pin 7 and see if that works.

[Azntuning]

Hey man, did you ever found a solution? I am trying to find the same answers. Everything in my cluster works beside the rpms.