Last week I left my windows down during a rain. I know a dumb thing to do with these vehicles. So now the left side radio control buttons do not work and no back lit buttons. The cruise control buttons work although no back lights on them. I removed the airbag because my horn was activating. I blew out the horn ring with compressed air and that fixed the horn problem. However I dismantled the left side control buttons and I did not observe any water or corrosion. Everything looks fine. I looked for a fuse but nothing obvious. I checked all the dash fuses and they are good.

Any ideas where to go from here? Everything worked fine before it got wet. I’m thinking something shorted out but I do t see anything obvious. The carpets did get wet which I dried but I don’t think it got wet enough to affect the connections behind the kick panels.

Thx

edit: the cruise control buttons are not working now either.

 

265 views. No one has a suggestion?

 

I dismantled the steering wheel checked all connections and the grounds at the wheel. Still nothing. I’m not sure where to check for power because I don’t know where the control wires are routed from.

 

Did you check the BCM module located in the front passenger foot well panel. If you left the window open, that's where I would start. It would also help if you had a scanner like the Schwaben to test individual components.

 

I have not checked the BCM yet. I understand from research that the steering wheel controls are connected through the K Bus. Do you know where the junctions are for the K Bus?

 

Which window did you leave open?

 

Here's the K-bus junction connection on my '06 R52......and this is what I found when I removed the passenger front seat and carpet

Bryan

 

I left both windows open. Everything works fine except the steering wheel controls and they worked fine until I left the windows open. I dried out the interior and the next day they didn’t work. I can’t imagine I have corrosion just from one incident. Seems almost like something shorter out. I will check tomorrow. Thanks for the help. Will report back when I find something.

 

Where is that K bus junction located?

 

Who are you asking? If it's me, did you read my post that has the two pictures??

Bryan

 

Yes I read the post but the pictures don’t provide a good reference point for where it’s at. Can you pin point the location?

 

Under the passenger front seat, half way between the center console and the door. Directly in front of the large square compartment that house's the HK amp in the R52 cars

This is where it's located in my '06, your results may vary

Bryan

 

Thanks!

 

Ok here’s the next development. I removed the pass seat and checked the wiring. Everything was dry and no signs of corrosion at any of the junctions is ncluding the BPM. I put it back together hooked up the battery and started the car. Still no controls working.

i then decided to remove the drivers seat. Disconnected battery removed seat removed from, lifted carpet and I found some moisture but no corrosion or broken wires. I checked the connections to everything and put it back together. Went to start car and no crank. Warning lights, bell chime but no crank. Checked battery voltage and it’s at 12. Hooked up my other vehicle to jump start and still no crank. Voltage reading 13v with other vehicle hooked to battery. What the hell?! All I did was lift the carpet and dry out the moisture. Wat could have happened?

 

I got it started. I knocked the clutch relay loose when I removed the kick panel. However still no steering wheel controls. It has to be related to water, but I’ve checked everything where water entered. Literally everything else on the car works normally except no steering wheel controls.

 

I had very similar symptoms, but not water-related....lost cruise control first, then lost radio controls. Just lived with it until my airbag light went on, at which point I pulled the clockspring, opened it up, and found that the wiring/tape coil inside had somehow gotten tangled and the wires were breaking. Could be the water messed up your spring somehow, could be it just chose that moment to go bad in order to throw you off the scent, could be the problem is elsewhere, but definitely worth checking.

 

Yeah that’s good advice. I was kind of working in that direction but couldn’t understand how a little water could get into a sealed clockspring. How did you get it open?

 

Edit: NOTE EDIT AT BOTTOM BEFORE DOING THIS!

There's a central collar held on by four plastic tabs, all easily accessible with a pick or skinny screwdriver or whatnot



Then the collar comes off



then there are nine tabs around the outside of the unit, all easy to get to...




and then it just opens up. Do it gently...it's not too hard to rewind the ribbons if they pop out, but still better to keep them in place if possible. If it looks like this one does, you've definitely found the problem....



EDIT: Note the piece visible above that has five rollers (one blue, four white) - BE SURE TO KEEP THAT PIECE HELD AGAINST THE RIBBON ROLL, AND HANDLE THE TWO PIECES AS ONE UNIT. Otherwise getting the ribbons routed correctly is far more challenging. You'll be able to see if the ribbons are detached from their connections (which are inside the black housing around the white roller unit above). Mine rather obviously are not attached. I got a replacement used on ebay for about $50.