auto to 5spd wiring question? Can't find answer in search.

[racingwoody]

If I swapped a motor, motor wiring harness, ECU and 5spd from a 90 325i 5 spd into an 89 auto and did not modify any wiring before trying to start for the first time would it cause the red/yellow wire going to the white relay in the aux relay panel in the eng compartment to burn up?

I tried starting the motor before remembering I had to splice the park switch wires, when I turned the ignition on white smoke poured from under the white relay next to the 2 yellow ones in the aux relay panel. The wire that burned up was red with a yellow stripe, it went into the same hole as a red wire with a blue stripe? On the auto wiring harness for the car the red with yellow stripe wire is not present, only the red with blue stripe.

Do I need to use the original wiring harness from the auto car or should my manual wiring harness work? Did it burn up because I did not splice the wires together and tried starting the car? Or am I facing a bigger issue with a ground or something somewhere?

Please help. Phone calls excepted. 614.725.8482

Thanks

[jlevie]

I suspect that the engine harness has suffered serious damage. The cause would be pin 20 of C101 being grounded on you car and the later harness having the wire to pin 20 being connected to the output of the main relay. Pull the harness, cut it open and look for wires with damaged insulation and repair as indicated. Or use the original harness. Cut the wire to pin 20 of C101 on the body side to avoid a repetition if you don't use the original harness.

[racingwoody]

I suspect that the engine harness has suffered serious damage. The cause would be pin 20 of C101 being grounded on you car and the later harness having the wire to pin 20 being connected to the output of the main relay. Pull the harness, cut it open and look for wires with damaged insulation and repair as indicated. Or use the original harness. Cut the wire to pin 20 of C101 on the body side to avoid a repetition if you don't use the original harness.

Got it answered. The wiring harness from the 1990 has a red with yellow stripe wire in pin 20 on the motor side of the harness c101 that connects at the firewall. This wire feeds into the white relay in the aux relay location in the engine bay. I believe it is something for the airbag. When using an airbag model engine harness with a non airbag harness at the fire wall you need to cut the brown wire going into the firewall side of the c101 hole 20 or a melted wire will result.

Thanks for the help Jim.

Started right up.