e30 s52 swap tach mpg temp gauge not working

[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.

[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.

[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]

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?

[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

[NickL]

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.

[duval7]

I dont think mine runs through the C104, from the ETM it looks like it goes through the C101 to the back of the cluster. Is that what you guys see in the diagram below? Also I cant find a three pin connector in that area. I had read that the C104 is on later models.

[NickL]

Its a white three pin connector in the glove box.

that's exactly how mine is hooked up - sans any issues

wire that goes to pin 24 on the x20 goes to the red/yellow wire of the c104
wire that goes to pin 14 on the x20 goes to the black wire of the c104
wire that goes to pin 20 of the x20 goes to the wire on the back of the instrument cluster in the circuit board with the green covering that snaps onto the cluster.

[duval7]

hey man for my tach to work theres a black wire that you need to connect to your c104. for me it was a black wire from the x20 (pin 8, not 100% sure) to the black wire on the c104 and my tach works

Where is the C104 located? Thanks.

[hooken m]

hey man for my tach to work theres a black wire that you need to connect to your c104. for me it was a black wire from the x20 (pin 8, not 100% sure) to the black wire on the c104 and my tach works

[duval7]

How is it wired through the C104? Does a wire from the engine harness need to be spliced into a wire from the C104? If so which wires? Thanks for the help.

[NickL]

^ tach needs wired through the c104

[328ijunkie]

Akg adapter doesn't encorporate a c104. You need one

[duval7]

So my temp gauge is working, i finished bleeding the cooling system and it eventually started to come up. I dont know if my speedometer is working as i havent been able to properly bleed my clutch and actually drive it, but my tach is definitely still not working.

[knuklehead92]

Yes I have the correct sensor for the coolant; e30 Browntop. I also wired it in correctly, slicing the BR/VL wire to the sensor. What are you supposed to do with the wires at the c103? nobody ever explains what you need to do with the c103 connector wires. Are they spliced into the engine harness?

ill check my car. its been a while since i looked it