tach

[e30-325]

i swapped a vanos m50 into my 89 325i automatic. my tach doesnt work. how do i fix it? i cant find the c104 plug because i dont think my car has it sooo what do i do? ive searched everywhere

[Wh33lhop]

Tach wire goes through the C101 on the later models I think.

[e30-325]

Tach wire goes through the C101 on the later models I think.

c101 is the round, e30 side of the wiring adapter correct?

[Wh33lhop]

Yes.

[e30-325]

well idfk why its not working. pin 9 from the m20 side is going to pin 20 on the 24v side like it should, fuses are good. no c104 connector in the glove box. one thing that is weird is that my service indicator lights are always on when the car is on. is that how it always used to be?

[MattM]

econoguage work?

[e30-325]

econoguage work?

no. econo and tach are the only things that dont work.

[SwiftE30]

bump. i am having the exact same issue and i cant figure it out. I redid 100% of my wiring today and made sure that they were all correct according to the ETM's

FYI: Caris 89 with 97 S52 OBD1 w 94 m50 harness.

[cormier]

Issue with the cluster itself? All the grounds attached?

[blacked_e30]

is the tach not working period or idleing too high? if idleing to high you have to change the switch on the cluster to a 6cyl

[SwiftE30]

tach is not working period, neither is my speedo or fuel consumption. what grounds for the cluster should i check?

[NbAmTwE]

go back and look for an XX/89 wiring diagram for your build month and do the same for s52 instead of following a guide if that's what your doing. It could just be a different connection for your chassis/drivetrain.

[SwiftE30]

i was looking at the 89 convertible ETM from wedophones, and the ETM for a 95 325i because that is what my harness came off of. I should check out an s52 ETM then? that doesnt make sense.

[328ijunkie]

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

See what happens.

[SwiftE30]

how do i go about doing this? Do i run it into the black wire at the back of the cluster, or at the x20/c101 plug? and do i just pigtail it into the pin47 wire?