Does anyone know what these are for??

[Sean T Sat]

simple question does anyone know what these wires are for or do?? i know there vital to my car running but i dont no y :D. they all are coming off the main harness or are were the main harness is by the ecu.

[Nicademus]

Can you take a pic from further out? Is this on passenger side or drivers?

[Sean T Sat]

Can you take a pic from further out? Is this on passenger side or drivers?

passangers (in the glove box) and yea ill upload them tomaro

[jlevie]

The three wire connector is for:

Blue/black - Tach output from the DME to the cluster
Green - Start input to the DME
White - Fuel consumption rate signal from the DME to the cluster

Single connector with the white tape tag is speed signal input to the DME

Single connector with the red tape tag is AC engaged signal into to the DME.

[Sean T Sat]

The three wire connector is for:

Blue/black - Tach output from the DME to the cluster
Green - Start input to the DME
White - Fuel consumption rate signal from the DME to the cluster

Single connector with the white tape tag is speed signal input to the DME

Single connector with the red tape tag is AC engaged signal into to the cluster.

i have the 3 prong connector on my 325is 1987 model but i don't have it on my 1990. any idea y that is?

[SpecM]

i have the 3 prong connector on my 325is 1987 model but i don't have it on my 1990. any idea y that is?

idle control module
Motronic 1.0 (eta) and 1.1 (97-88 i) had them, motronic 1.3 (in 89+ cars) had that funtion intergrated into the DME

[Sean T Sat]

idle control module
Motronic 1.0 (eta) and 1.1 (97-88 i) had them, motronic 1.3 (in 89+ cars) had that funtion intergrated into the DME

i did an egnine swap do i have to upgrade to a moto 1.3 or can i downgrade the car?

[Sean T Sat]

o yea and wuts a DME???

[jlevie]

The only other engine harness variant that I've seen has two four pin connectors, one white and one black. For that variant:

Black connector:

Violet/black - AC on input to the DME (to pin 40)
Violet/blue - AC on input to the DME (to pin 41)

White connector:

Violet/red - Automatic transmission range switch (to pin 42)
Green/black - I never figured out where this went, only that it didn't go to the DME connector
Brown - to pin 33 (ground)

On that harness the tach, fuel rate signal, and start input signal go to the C101 connector.

[Sean T Sat]

The only other engine harness variant that I've seen has two four pin connectors, one white and one black. For that variant:

Black connector:

Violet/black - AC on input to the DME (to pin 40)
Violet/blue - AC on input to the DME (to pin 41)

White connector:

Violet/red - Automatic transmission range switch (to pin 42)
Green/black - I never figured out where this went, only that it didn't go to the DME connector
Brown - to pin 33 (ground)

On that harness the tach, fuel rate signal, and start input signal go to the C101 connector.

how do i make the harness work with the car?

[Sean T Sat]

nobody knows??

[DaveSmed]

The three pin connector. Put +12v to the green wire. Try to start your car.

If you did everything else correctly, it will start.

As mentioned elsewhere in the thread, the other wires in that connector are important as well, BUT the late model harness ran it through C101. You will not have tach or fuel rate until you fix it.