I'm currently in the process of building this car:
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I can't help but feel cheeky coming on to an owner's forum looking for help when I'm working on the car in a professional capacity, but I'm stuck in a rut!
Basically, I'm converting a 2000 320i Auto (LHD) into an M3 Touring using a 2005 M3 CS SMG (RHD) as a donor car (the donor was a catD repair job....mechanically good, but average body repair underneath!)
I've got all the engine, gearbox, suspension, brakes....even the boot floor switched over, and so far everything is looking good. I seem to have the gearbox selecting as it's supposed to and all the engine systems seem to be live.
I've got a problem though.....it won't turn over on the key!
Points worth noting:
* I've done an M3 conversion into an E46 Touring before, though it was a manual car. I did have an issue of non-cranking where I fitted the DME and key from the donor car, but not the EWS module as I wasn't aware of it. Once I'd changed that, it fired up.
* On this car I'd fitted the M3 DME, but left the original key and EWS as I (wrongly) read that the key and the EWS are the immobiliser system....the DME wasn't part of it.
* On learning the DME does need to match the EWS module, I switched that over from the M3 too. So now I have the key, the EWS and the DME all from the same car.
* I've spoken to a local well-regarded BMW specialist (we aren't BMW specialists, we've only ever done these conversions!) who's informed me that having mismatched the EWS & DME already is no issue. I'd rang them after reading on a forum in the USA that I might need to get it all re-coded together. He assured me that was bollocks, and that as long as all the right components are in place, it should work. Unless there's a wiring fault......
.....So today I've been spending time investigating by looking at the wiring diagrams again, and I've noticed something I can't explain. On the EWS pinouts, according to the WDS diagrams, pin2 is supposed to be the trigger to the starter solenoid (as the EWS effectively acts as a starter relay). It's a black/blue wire. Again, according to the WDS circuit diagrams, this is the same for the M3. However, the M3 has an additional wire to pin 3 (also black/blue), which is not shown on the 320i diagrams. According to the list, this goes to fuse 22 (5A) in the fuse box, which I've fitted (I can't remember what goes on the other end, but that's in there too). All the wiring in the fuse box has been fitted as it would be in the M3.
Still with me?! So all I would (in theory) need to do here is hook up the wire to pin3 on the EWS plug, and there you go. According to the wiring diagrams, that's it.
Only it's not; the 320i never had a wire going to pin2......it had this single black/blue wire heading straight to pin3, a pin which according to the WDS is not used.
I've no reason to suspect it's ever been tampered with, and the Touring ran fine before it was stripped down. My issue could well lie elsewhere, but until I can work out what's going on with these two wires I could be chasing my tail.
Any advice/knowledge/assistance would be greatly received. BMW dealers (unsurprisingly) don't want to know!