Had my sunroof drains leak when I bought the car in 2021. Dropped the headliner and reconnected it, no issues.

This winter I replaced the clutch and when I got the car back together check engine light was on, my code reader won't communicate with the car, it gets power from OBDII port but no coms. Weird, but I disconnect the battery for a bit, resets everything and light is gone. Drive the car 1000+ miles on new clutch no issues.

Recently I get check engine light, with airbag, and seatbelt lights while I am buckled. Pushing the clutch in while driving is activating some relay I can hear clicking. Turn signal light on dash will stay on for minutes after I cancel the signal, or not turn on at all but I can see externally that the lights are working.

So I go check all the fuses, no problems there. Take off the left side panel by the fuse box because I suspect the water that got in years ago down that A pillar has done damage.




Nothing wrong here! What do I check next?

You'll notice someone has been here before too based on the butt connectors and zip ties. Wiggling this connector gets me back to near perfect operation of the car. But 1 pin is completely corroded away, which might be my data line for obdii. I cleaned it up a bit with some contact cleaner and DeoxIT, but I don't think there is any bringing this back.

I bought a salvage connector on ebay with wire pigtails just cut out of a vehicle, going to try to splice that in, not sure if that is the best approach. Would like to find the pins to buy, put new pins on the existing wires cut shorter to bypass the corrosion and put those into my new salvage connectors.

Thoughts?

 

I'm shocked nobody has written you back. Someone posted in another thread that the only point of this connector is to help in the assembly of the car. That said, your corrosion is way worse than mine. Pics below.

I would just cut out the wires and just connect them up. I purchased a set of these heat gun solder/shrink wrap combination inline connectors 4 years ago and never used them. Well now would be a good time to use them.

I cleaned them up but I still have an issue. My clue is that the round 10-pin connector just behind the driver side headlamp had brown water pour out of it when I disconnected it initially. I am going to jump those 10 wires using this method first and see what happens. In 18 years of owning this car (06 PW/B) and my 06 GP I have never had to disconnect either one of these connectors. So it's not like a maintenance thing that you need to unplug all the time. That said it does help in troubleshooting although I am thoroughly confused because I have been getting some weird behavior.

How did it turn out for you?

 

Also watching this guy's video and reading this thread was very very informative. I have since purchased a breakout box, an led test light, a digital multimeter, a probe set, and have dismantled the damn car in trying to figure out why I also cannot connect to the DME. I am able to connect to other modules and obviously have power and ground at the DLC/OBDII port but I cannot connect to the Kline (diagnostic bus) but the car drives perfectly fine with no codes. That would indicate an issue with the diagnostic bus and not the CAN bus. The main wire that needs focus is the purplse wire with the white stripe. That's goes to each of the modules and then gets sent back to pin 7 on the DLC port. If there is a break in the wire and/or a short to ground you can send a small 12v signal (watch the guy's video) and it will light up indicating a short to ground.

When I disconnected the cylindrical connector behind the headlamp I no longer showed a short to ground. I still haven't figured it out yet but I will.

Read the @waystedman post and watch his video.

https://www.northamericanmotoring.co...ound-help.html

 

Grant, I like your initial idea. Find the correct pins, Call Way Motor Works in Atlanta as they work on these cars every day and I'm sure could guide you to the correct pins and crimp tool. Use the salvage connectors and you should be good.

 

I had seen that video previously, really informative. My round connector under the hood looks fine, although I haven't done any continuity test. Recently did the clutch on the car so a lot of the wiring under the hood I undid and checked over, reassembled everything with some dielectric grease on the connectors so it comes apart easily for me or the next guy.

Haven't had time to fix it, maybe I will just get rid of the connector and splice everything direct, I can always add it back in once I source the pins it uses and do it real clean.

 

I watched the video, It was informative thank you so much for sharing.


 

Little update, I have everything mostly working again. Two wires don't match up in the 42 pin connector, I have a yellow wire with a black stripe (not part of the twisted pair ylw/blk and ylw/brn) which I believe is coming from the chassis side, and on the dash side of the connector a blue with yellow stripe wire , everything else has a match. The rear window defrost light doesn't come on, that is the only thing not working.

Other than the crank no start issue. I have ability to read codes again, and have a DME, EWS incorrect code (P1656) Car will crank, at least some fuel is in the rail, no spark. From what I am reading I need to sync the DME/EWS. I had unplugged that 42 pin connector and the battery a bunch so maybe that caused the issue?

Ordered a cable off ebay and will try to get INPA working? Is this the right path?

 

These two mismatched wires were the rear window defrost. The LED comes on the A/C control panel and I hear a relay click. I don't really have a way to see if it's heating though.

I bought an Autel MK808BT on sale, used that to fix my P1656 code and it starts right up now. So I think everything is working on this car again!

 

Hey guys, I just spliced in a new connector (I wish I had realized I could have just directly spliced the wires, would have saved me hours and frustration) and I’m still having problems and need some help. My original issue was that my whole dash wouldn’t turn on and various issues with my brake lights always staying on, the 42 pin connector had been corroded from water damage form the sunroof drain, and now almost everything works like it did except for a few things: my speedometer and tachometer won’t turn on, the engine temperature gauge doesn’t work correctly and a few indicator lights like my traction control and brake indicator stay on. I’m pretty sure the issue is that I connected some wires to the wrong ones on the splice, some look very similar to others, but because I correctly connected some of them it seems, I don’t know where to start looking for the wires I need to switch. Does anyone know which wire is responsible for the speedometer? That’s the one I’m most worried about fixing so that I can drive my car, the behind the wheel gauges still light up just don’t measure anything.

I’m starting to get my wits end with this project, having someone else fix it is far too expensive to be worth it, any help would be greatly appreciated.

 

First of all, sorry about having to deal with this. Been there done that, still living with intermittent issues.

@GrantG I also had DME / EWS communication issues, with crank and no start. Spent 700$CAD on a new factory programmed EWS, and key fob. Could not for the life of me get them talking and aligned again. Instead of digging through wiring, connectors, modules, yada yada... i decided to send the ECU off to "rpmmotorsport" in Vancouver and have the EWS permanently bypassed. Started up and runs fine for 3 years now. I did not see it worth investing more time, effort and money into fixing the EWS issue, as there was signs of water damage like yourselves. All it takes is one wire not making proper connection and your back in the same situation spending more time, effort and money on an issue likely to return yet again. Had i have known about RPM i would have saved the 700$ spent at BMW to just have the EWS deleted in the first place.

@SuprDuprCooper There is a pinout available for the 42 pin connector, from a glance there is no odd combination of wires (like red wire to a yellow). I am going to assume that you have a couple wires crossed. It may be in your best interest to delete the connector start from scratch taking the time to ensure all wires match. Attached the pinout from another forum.

Best of luck both!

 

Thanks, I came across them(RPM) when I was working on this but there is a sync function in my autel tool that got the ews and ECU happy talking again. Haven't had an issue since.

 

This was ugly - but this stuff can be helpful too

https://caig.com/deoxit-d-series/

 

Finally decided to tackle the corrosion this water damage left. Some pictures.


Pulled the carpet up. Lots of rust.

Wire brush and some mineral spirits to clean it up.

A few coats of Eastwood rust encapsulator.

Hopefully that keeps it in check for a few years.

Finally got the remote unlock key functions working today too so now electrically it is 100% working. Turns out I think I had the wrong year mirror/radio receiver that I ordered when I first found the water damage and finally tried swapping the mirror from my other R53. Still didn't work and had no luck with the key initialization instructions but my Autel had a function to log on new keys, which doesn't seem like it did anything but they started working. I ordered a mirror from an 05 off ebay with auto dimming and homelink too so hopefully that solves it permanently.

 

Looks really good ... makes me add a few tasks to my list of things to do to mine.

Motor On!