SMG under-dash/instrument panel clutch switch connectors

[Papermaker]

Hi all--

I've just about finished a SMG to Manual M3 conversion. I purchased a ’04 SMG M3 last fall from a local dealer after it stopped moving under its own power (it was thought that the SMG pump failed). While removing the transmission I found that real reason the car stopped moving, mice had chewed through the SMG harness wires at the transmission and clutch hydraulic actuators. I’d already ordered the parts and decided to complete the conversion even though I could have fixed the mice damage wiring and driven the car as an SMG. So, to keep the project moving, I repaired the mice damaged harness and left it in the car. I also purchased a manual transmission harness, planning to swap it in after I had the car back on the road (I purchased the manual harness to sidestep any issues related to the mice damaged/repaired original). The car runs and drives well after coding by a local Tech.

Last week I installed the manual harnesses and everything works normally except the clock now displays “** ll **”. The only thing left to do is to finish the clutch switch/cruise control function. I originally hardwired the clutch switch power, ground and EWS wires and pulled the cruise control wire up to the e-box. Now here’s the question, Has anyone ever heard of or seen clutch switch connectors in the under-dash harness on a SMG M3? While the tech was coding the car he mentioned that the manual and SMG dash/instrument panel wiring harnesses are the same and that both include clutch position switch connectors (his comment makes perfect sense to me). So, it should be simple to connect the dash/instrument and clutch switch harness connectors together (I’d still have to hardwire in the EWS wire). Now, according to the tech all I have to do was find the tied back dash/instrument harness clutch switch connectors and connect them to the clutch switch harness (the Tech also said that the EWS wire is tied back into the harness somewhere near the EWS connector).

I’ve spent most of the day looking for the tied back connectors without any luck! I’ve read a lot of threads describing the SMG to manual swap and I’ve never seen a comment about using the existing dash/instrument panel connectors to wire in the clutch switch! Has anyone read or run across a SMG conversion that used the existing instrument harness to connect their clutch position switches? Does anyone have access to a under dash harness that they can check/find the connectors if they are there (pictures would be great!)? Also, if possible, can someone with a manual transmission M3 check which way the clutch switch harness is routed, does it enter the dash harness along the firewall or does it join the instrument panel harness?

Any help would be really appreciated,

Thanks!

Papermaker

[BMW_QAS]

I just finished my swap as well. You’ll spend more time looking for the wiring than actually just running the wires individually. Also if you run the wires you’ll know where to look when trouble ensues. If you DO find the mythical beast, post a location under the dash where you find it. My guess is that the SMG under dash harness is different otherwise the factory would have wired in the clutch and GPS wiring to the ECU plug (and left it lose on the other end). Good luck and have fun rowing them gears.

-Steve

[Papermaker]

Hi BMW_QAS--

I was just planning to post my clutch switch harness findings. I worked with Jason Reighard at Get BMW Parts to determine if the SMG and Manual under-dash harness part numbers were the same. We weren’t able to find either a SMG or Manual under-dash harness and finally decided that the harness is a part of the main chassis harness.

The M3 had two main chassis harnesses, the first is NLA, a part number is not available. The current harness part number is main wiring harness, 61116940113. It’s Jason’s and my opinion that the under-dash harness and the clutch switch harness are part of the main chassis harness. The clutch switch harness has to be there!

So, reinvigorate by the knowledge the harness is there, I searched the net endlessly for photos of the clutch and brake master cylinders, clutch switch and the harness hoping to see where the clutch switch harness entered the main harness. After a through search for that photograph, I just couldn’t find it. If an M3 owner with a factory manual transmission could grab a photo of the clutch switch harness while they are under the dash, possibly changing the clutch or brake master cylinder, it sure would shed light on the harnesses location and probably answer the question, where is the clutch switch harness! And, you’d also be a hero to the M3 SMG to Manual conversion community!

I did come close to finding the photo! I went to the Source and found this in the TIS. https://www.newtis.info/tisv2/a/en/e...616032/VIetxlP Although the clutch switch harness is clearly there in the photo, I didn’t remember my main harness looking like the photo when I hardwired the clutch switch to the EWS and pulled the clutch position wire up to the e-box. So, I took off the under-dash kick panel again only to find that the harness in my ’04 M3 runs from the firewall horizontally directly under the dash. I think that photo below is the NLA main harness.



Still thinking the clutch switch harness had to be there I took out the seat again and laid on my back looking at the damn main harness from the firewall to the dash and instrument panel for another hour or two. I give up, I can’t find the clutch switch harness! I made the clutch position switch hardwire connection in the e-box.

I hope the next person that goes looking for the harness has better luck them me,

--John

[terra]

It's not unusual for replacement parts from BMW having connections for all options, while at the factory they had separate harnesses for different options.

If your car was prewired, then your EWS module should already have the extra wire going to it for the start lock and your instrument cluster should already have the wire from the reverse signal. To my knowledge, this is generally not the case.

[Papermaker]

Hi terra--

Very good points! My EWS was not pre-wired so your factory specific harness makes a lot of sense. The manual transmission gear position wiring isn't there as far as I know either.

--John