Tach not working. Can't find answers.

[SwiftE30]

I've searched and searched and read and read about peoples problems with the tach not working and i cannot find an answer to mine not working.

89 vert with 97 s52 w/ 95 325i harness.

Pins:

c101 pin9 to x20 pin20; engine speed output
c101 pin14 to x20 pin 14; vehicle speed output.

I have checked these with each ETMand confirmed that these are what they are. And my tach is still not working.

Any auggestions? My tach worked fine before the swap.

[328ijunkie]

run a ghetto wire from the ECU pin: 47 to the cluster pin: 7 on connector C1 (black wire)

See what happens.

[SwiftE30]

do i just pigtail the wire into pin 47 wire at the ECU? then to the black wire at the back of the instrument cluster or the black wire at the x20c101 plug?

im familiar with the wiring process just not bypassing anything like this. thanks for the help

[bimmerteck]

Which DME are you using?

the pins on the DME connector are different for different years of engine management.

[SwiftE30]

dme is from a 1995 325is, red label 413

[bimmerteck]

dme is from a 1995 325is, red label 413

cool, can you test for continuity from pin 47 on the DME connector to pin 20 of your x20?