S52 Wiring Harness - Removing Auto Tranny Question

[Boise]

I have a 97 s52 harness that I have removed most of the wiring for the auto transmission from and I had a few wires I was not sure about. I have three wires that go from the Transmission Control Module to the Engine Control Module (DME). They are:

Black, pin 85 on the tranny module, and the ETM states its description is "CAN LOW"

Yellow, pin 86, description is "CAN HIGH"

Brown, and I don't see a brown wire on the ETM between the two modules.

My questions are, can I clip the black and yellow wires? And what the heck is the brown wire (ground???) and can I clip it too?

Here they are...pics for clicks

[Boise]

I forgot about one more. I have a Blue/Green wire that came off of the Tranny Module pin 60 called the Data Link Connector. It is spliced and one lead goes to the DME and I think the other goes somewhere else (I am guessing the x20 style diagnostic port)

[Mr.SWISS]

If in doubt just wrap them up. but if they aren't connected to anything then that's like they are cut in essence. The circuit is not complete......

You can defiantly remove one of those huge 12V wires you only need one for the starter the e30 has it's own fuse power cable on the firewall.

I used an auto harness on my obd2 Z3 swap ( M44-M52) and just wrapped most of them and zip tied them. Used with a manual MS41 DME w/ EWS delete I didnt have any CEL's.

[jim325]

Id guess the can low and can high are used between the dme and tranny module for communication and diagnostics.

If your not using an auto trans then you shouldnt need them. They likley dont have a corresponding pin in a manual vehicles dme.

If I remember correctly can stands for controller area network. Just a way for modules to communicate between eachother.

[Boise]

Thanks for the responses guys. Anyone have a clue what the brown wire is for? I don't see it listed in the ETM.

[NbAmTwE]

CAN HIGH, CAN LOW, and DATA wires should lead to the ignition on a 97 m3. It would normally be hooked up to the BCM in the m3's dash. There shouldn't be any reason you would need these data wires for your swap since you'll be using e30 cabin wiring.
Like stated before, no need for them just wrap them off.