StreetForged
Member
- Joined
- May 24, 2018
I wired up an Ebay tach to my 1990 240DL last night and I couldnt get the needle to move, though the lights worked. It has a red(power?), white(light), black(ground), and green wire(Tach), which I've hooked up in the corresponding way:
-Red wire i tested on both the battery and on what i believe to be the positive post on the coil
-White is spliced onto one of the fuses on the fusebox under the steering wheel, can't remember which
-Black is grounded to a bolt on the chassis near the fuse box
-Green I have tried hooking up to both the blue wires on the coil, and the red and white wire behind the gauge cluster that I believe is for the OEM tach?
I have done some research to get this far, but at this point I'm just assuming the tach itself is a dud. I have installed two of these on other cars before and haven't had this same issue, but I could have done something wrong and figured someone else might have more of a clue than me.
-Red wire i tested on both the battery and on what i believe to be the positive post on the coil
-White is spliced onto one of the fuses on the fusebox under the steering wheel, can't remember which
-Black is grounded to a bolt on the chassis near the fuse box
-Green I have tried hooking up to both the blue wires on the coil, and the red and white wire behind the gauge cluster that I believe is for the OEM tach?
I have done some research to get this far, but at this point I'm just assuming the tach itself is a dud. I have installed two of these on other cars before and haven't had this same issue, but I could have done something wrong and figured someone else might have more of a clue than me.