Tach no work! :(

[Kozworth]

Paging jlevie..

The Bentley has a pitiful list of wiring diagrams. I had an eta and swapped a b25. I have no tach. Anyone got a diagram of the power flow to the gauge?

Also the two wire harness thru the shifter bushing boot to the trans is ripped. I am pretty sure this was a reverse light harness but can anyone confirm this?

[Gregs///M]

Download the ETM (electronic troubleshooting manual) It has schematics for everything.

Your tach signal comes via DME black wire in the blue connector (behind cluster.) It will have a 1.5-6 volt AC voltage signal while the car is running.

[jlevie]

The tachometer (and econometer) signal on your car reached the cluster via a connector (C104) pigtailed off the engine harness near the DME connector. Only an engine harness from a 325is made between 9/86 and 8/87 will have that connector. Later production routes those signals through C101. The easy fix is to graft the C104 connector to your engine harness.