Total electronics freak-out: 2002 330Cic w/73k miles. Can't even read codes

[Redshift]

Hey all - I'm a bit flustered so I'll ask for help from the community. Recently, my wife was complaining that her daily driver '02 330Cic (we bought this car new and have owned it since April 2002) with 73k miles on it started having issues on the cluster. The DSC and BRAKE and ABS lights would, in some combination or other, always be on.

I realized the battery was getting old and I replaced it. Alternator outputs 14.2V and new battery seems to stay charged.

Last night I drove it and the ABS, DSC, BRAKE lights were all on...the speedo worked but the driver's side headlight didn't. Sometimes the speedo will not work either.

The top also won't go down at the present moment and the driver's seat stopped moving. I had to unplug the battery and wait til the hard reset occurred, then the seat moved after that but only once.

Any ideas what module could be going bad? We can't even read codes - no tools will communicate with the car over OBD2.

[dworthy]

When the speedometer drops out, that will be the right rear sensor going bad. That will also cause the "trifecta" of lights to come on.

As for the OBD-II stuff not working, what are you using to connect to it?

I would go back and ensure the battery connections are tight, just a thought.

Lastly, I like your M-builds

[Redshift]

Thank you, Worthy.

Because all of this happened all at once wouldn't you suspect a module rather than something else? It was all working fine - no issues whatsoever before, then all of the things all at once. The intermittent nature of it all seems odd also.

OBD2 - I am using various things - INPA, ISTA+, and Carly - two different adapters and a few different programs. Note that those programs and adapters work on the other cars without issue.

[dhurley34]

BUS failure?

[dworthy]

Well you can try a hard reset, which is designed to drain all the modules of power. You have to remove the pos and neg from the battery and connect them for about 5-10 seconds. You will see a small spark, and then you can reconnect them back to the battery.

If that doesn't work, I would start looking at the fuses, and like noted above the BUS.

[Redshift]

I'm not familiar with BUS failure - but will do a search. Thank you so far for your responses. (and thank you for your comments on my touring builds, Worthy)

[TonyAngel]

Redshift, check out this thread....https://www.bimmerforums.com/forum/s...g-thing-Thanks

He was having trouble with the lights and failure to communicate as well. He had a bunch of problems to work through, but the communication problem seemed to be a faulty sensor (steering angle in his case), but some good info and sounds like problems similar to yours.

[Redshift]

Redshift, check out this thread....https://www.bimmerforums.com/forum/s...g-thing-Thanks

He was having trouble with the lights and failure to communicate as well. He had a bunch of problems to work through, but the communication problem seemed to be a faulty sensor (steering angle in his case), but some good info and sounds like problems similar to yours.

Thanks, Tony. Looks like mine is very similar. Took it to my friend in town who's a side mechanic and he traced two problems on the bus -

1) Left side xenon control unit
2) Steering angle sensor

Both were dragging down the bus voltage causing a communication error. When those two items were removed, the bus acted normally again. So I've got FCP working on a price match for the steering angle sensor and I believe the xenon control units I took out of my M3 wagon build car will work on the 330 so I have those at the ready also.

Once those are solved, hopefully he can also help figure out what's up with the driver's seat and passenger's seat. Those issues have been ongoing.

As a side note, I asked him to double check the drains and they are fine, and we don't think any water got into anywhere so this could just be a sensor failure.

Will report back when I know more.

Brian

[dworthy]

Yes, the steering angle sensor can cause communication problems, and I have also found oddly enough that the oil level sensor can do it as well.

[TonyAngel]

Red, it sounds like you're on the road to figuring this out. Good deal.

You have some nice toys, BTW.

[Redshift]

Hey guys, just following back up on this. Turns out the headlight control module (xenon) and also the steering angle sensor were both bad, causing the bus to fail and all the other issues.

My friend expertly diagnosed and repaired both. Then he figured out why the seat was wonky, replacing 2 motors and a control unit, and we are back to zero error messages on the dash for the first time in years.

I just need to code the SAS and then it's ready to go another 75k (fingers crossed).