Auto loom modification to allow ECU to start engine

[rubadubdub]

Hi guys, im new to e30zone and am currently working on an M60 (94, 540 auto) conversion into a friends E24 with a manual 540 box.

I've got most of the wiring sorted thanks to the info and links off here.

The one I'm stuck with is the auto loom modification to trick the ecu into thinking its in neutral not park.

The ECU wiring diagram suggests there are only 3 connections directly to the auto transmission control module:
84 - shield/ground
85 - yellow input/output CAN-L
86 - black input/ouput CAN- H

Does anyone know what signals these pins receive? I'm hoping its as simple as a 12v to one or both, although i'm confused as to how they can be both input and ouput.

If anyone has got the auto loom to work and can give me some pointers I'd be very grateful. I noticed driftben asking about this a while back, did you get this sorted?

[chips]

I'd also like to know

[rubadubdub]

I think I've worked it out...
The bit which looks like it'd prevent starting is on the starting circuit. Its called the starter immobilisation relay (k1w). It bridges the gap between the ignition and starter and only starts if the transmission range switch is in the right place. A yellow/black 2.5 wire goes in and out.

I'm still not 100% convinced this is the one as I dont know why people would have swapped this much of the main loom over. If you just match up the wires on x20/c101 surely this section is never transplanted over anyway. That said, in my case the E24 recipient is an automatic so it'll have to be bypassed to work on an manual box.

Does this sound right or am i still barking up the wrong tree? Have to travel 100 miles to fit this so would rather work it all out beforehand.


Here's another thread that talks about it:

http://www.e30zone.net/modules.php?name ... &start=225

[SHAZ325iSPORT]

I joined the yellow and black wires together.

Started fine,everytime

[rubadubdub]

Thanks guys. I'd pretty much come to the same conclusion by going over the diagrams again. The confusion started due to 1) too many yellow and black wires (CAN bus inputs are yellow/black too). 2) a few comments I'd read that I thought suggested the ecu affected starting such as :

[QUOTE] from the linked thread:
I've both looms in my garage, basically they're identical though the auto-loom has couple more wires & second big connector for the autobox ECU. The autobox-loom needs some fiddling (when using stock ECU and manual box) to get the car started, otherwise all the information goes (if i've understood correctly) from main ECU to auto-ECU so it doesn't affect performance other than starting. [QUOTE]


With hindsight I think the references to loom fiddling were all were talking about the auto starter relay bypass, nothing to do with the engine side of the autobox loom.

Once the mounts are sorted and engine goes in I'll take some pics. Everyone likes a good build thread

[Jonsku]

I'm in middle of E30 V8 autobox swap. As said, the "autobox ECU" does not affect the starting / driving the car in manual mode in any way.
The only thing that needs to be taken care of is that the wiring loom thinks that the car is at "P" all the time => you need to check the wires on the two big connectors near ECU-connectors (and also the drive-away protection (black-violet) in case you have one..)

[Driftben]

im a stone throw away from starting mine and all i have done is joined the yellow and black cores together from the cable that joins the Engine ECU to the Autobox ECU. ill report how that goes

[Driftben]

well i have managed to get mine to turn over but it wont start? no power to the fuel pumps or anything really? would this be anything to do with this 'drive away protection'?

[Jonsku]

That might very well be the case.

Check pin 66 at ECU, if I remember correctly it is the drive-away protection..

[Driftben]

I had a feeling it might of, what am I looking for at pin 66? Continuity or voltage?

[Jonsku]

I had a feeling it might of, what am I looking for at pin 66? Continuity or voltage?

It's input to the ECU, not sure which one is "ok to start"


Did you figure this out?

[Driftben]

well it kinda sorted its self out, started fine and all is well.
all relays pulled in and fired up. all i done was twisted the black and yellow cores together and wala.

thanks for your help matey