nelsonmx

I'm a bit late on this but......This morning I go out to run an errand and I get the Brake Proportioning Fault and locked in park. Check the drivers carpet and sure enough it's quite damp. I pull it up and there is a small amount of water so I vacuum it up. When I take the tape of the wire loom everything looks good. When I peel off the "hockey tape" it is also looking OK.....There are in my case 4 or 5 wire joins just above floor level. They are all crimped bare splices, so I assume these are factory.....The last one I check is a brown wire and it is corroded and the wire join is gone. Long story short, I stripped both wires, twisted them and soldered them back together and I'm back on the road. Now my next quest is to find out where the water came from....I suppose I'll look at cleaning the sunroof and other drains.....
As always, thanks everyone for the helpful posts!!
Brgds,
Bob

Fabianrou

This is the passenger side I did when I had a lagoon in there because of clogged drains. Are the cables that get corroded located in the same spot as the ones

you see here in the passenger side or higher up toward the engine?

Fabianrou

'04 Cayenne S. Just got the Brake Prop. gremlin tonight. Could you tell me exactly where the wires are that people refer to. Are they higher up toward the "dead pedal" area or lower toward the seat in the same area as in the passenger side in the picture? As you can see I've had the dreaded flooding in the passenger side but I've never been under the driver's side area carpet. Thanks :-)

touareg

Does anyone have a write up on this? Hoping so as time has passed, seems to be a common problem when you get the "Porsche Cayenne ignition lock fault, brake proportioning valve failure, press brake pedal problems" on the MFI.

touareg

I know this is old, but I had water coming in from the door wiring harness that leaves the body.

I am drying it all out, and I hope it was just a temporary thing as I was able to fix the leak.

touareg

Wow, this got a lot worse, car would start, but got ignition lock malfunction, gear select malfunction, suspension fault and had ABS, Brake, Check Engine and a few more I forgot on top of the Brake Proportioning.

I had to rip the center console out, to move the lock out of the way and get it out of park.

BTW if you have a 2008-2010 you only need to remove the center console cover, not the shifter cover, etc to release the lock, completely different than the 2003 to 2006 models. Found this out after I ripped out the foam, shifter, cover plates, etc.

I was able to drive the car home in limp mode, 1 gear, no MFI, my Brake lights did not work (Found that out after I got home and was suspicious when I saw people like 10 car lengths behind me!)

Anyways, after 30 minute drive I got home, started to put the basics back together and leave it open enough so I can put it in neutral for a tow to the shop, then I heard a bunch of clicking and the car went back to normal!

I hope it was just moisture, not sure how to proceed now...

touareg

Are you getting all these errors when you try to start the car? Press Brake Pedal, and you pressed it?

Christmas tree on the dash?

Ignition Lock Failure, Brake proportioning Warning, ABS light, Traction Control, Check Engine, Brake Light Flashing. Stuck in Park May or May not start.

I had water leaking in from the door to body grommet/hose. If your carpet is wet or damp, this is most likely the result of a small leak for a long time.





One person mention that relay 443 on top of the battery may be the culprit if you don't have a water problem.

So you have got all these on at once, car may or may not start. If you can get it to start, you are not stuck, but are in a limp mode. You can also put it in neutral for a tow.

You can remove the dual Allen wrench under the rubber mat in the bottom cubby.

Remove the two Allen screws, that you can see from that cubby towards the front of the car. Lift the center console surround, it snaps out from the back towards the front, with the front slotted in under the ash tray.

With a long tool, look in front of the shifter, you will see in my case, a 2009 Cayenne a red arm that moves the lock, press it gently to the left and you can now shift out of park.

WARNING: Your brake lights will not work and you can not leave 2nd (I think, gear) if you drive the car this way. I am not sure what else may not work from a lighting perspective.

Now if you want to fix it:

First, pull out the drivers and rear passenger mats if you have them on the Driver's side.

Behind the drivers seat, slide out the plastic beauty covers of the left and right rails.

Remove the two plastic covers, just in front of the Drivers seat base, and with a 5 point bit, remove both the screws that hold the seat in place. If you are having trouble with this, it is the same procedure to get at the battery.

Next, slide the seat all the way back, and then tilt the seat back forward.

Now, push the seat head rest with your hand back, the seat should now pivot on the rear hinges and tilt back.

Slide the forward with the power switch, and the seat will move out of your way even more. You can reverse all this later when you put the seat back, this method just avoids hitting the steering wheel.

Now, you do not need to open the battery box, just remove the nut from the ground cable, next to the seat bolt for the transmission tunnel, get a back and wrap it around the end of the cable, I used a rubber band for good measure. This will keep you from accidentally applying power.





Now the only hard part, you need to pry up the carpet, and it is a little tricky because we will not be removed the door sill.

Start from the B pillar, under the door sill, this will give you some flex in the carpet, when you try to remove the dead pedal section of the carpet.





Once you have it out from under the door sill, you can prop it up, I used a 32oz plastic cup.

Now is a good time to dry any water, etc from under there. My car would still start, so I ran the car on idle, high heat, full re-circ, and floor only for 3 hours.

Now we can open the flat plastic wire protector. Just release the tabs with a small screw driver, then fold it back, towards the door. You again may find tape, or a weight of some sort to hold it open.







So the cloth is multi layer and I assume was at some point sticky on the bundle. You can unwrap the end, right where it enters the flat black wire protector. That lets you peel back several strips of cloth that run parallel with the wires. Another pieces is wrapped around the wires circularly, no need to disturb that.





You will find 3 pairs of wires, in my case one was crimped and had a plastic protector. 2 were connected somehow, with cloth electric tape wrapped around the twisted pairs. One just pulled off and I had plastic wire stubs, the inside was corroded to copper dust!





The other looked fine.

So the problem is two fold, 1 they are lousy connections, 2, they sit at the bottom of the bundle, right where water would pool and absorb into the black wrap. You could see the corrosion on the black wrap in my case, so I had a pretty good idea, plus when the car was on and I pressed that spot, more alarm dings flashed!





I pulled all three pairs of the crimped wires, and moved them further up in the bundle, under the dead petal, so I could get slack and re-locate them later.





The bad red wires I striped back 1 inch, clipped the corrosion off, butt joined and soldered them with shrink tube, then folded over and wrapped in electrical tape.








The good black wire, I still pulled the electrical tape, shrink tubed it, folded over the remaining shrink tube, and electrical taped it, with zip tie to hold the tape down.





Finally I tucked all 3 wires on the top of the bundle, under the factory zip tie behind the dead pedal, and zip tied them to the bundle. This way if water gets in I have to have 4 or 5 inches of water for it to sit there for a long time and repeat what happened.





I was able to nicely put the fabric electrical tape together, zip tie it in several places, and tuck it all back in.



Pushed the carpet back in, connected the battery, car started no problem few errors, but all cleared except the check engine light after a short drive and putting my seat back in.

This really should be a recall.

Took me about 1.5 - 2 hours to complete.

Nestor J V

I got the same issue and when I looked, it was soaked as well. My issue is that this is what I found... An open end. Can anyone give me some advise on how to find out where they are supposed to connect to? I'll be checking the and redoing those bad repairs you see.

Nestor J V

Thank you all. What you guys said in this fix, fixed my Cayenne S. Again. You all are appreciated.

nelsonmx

Went out to start my 2004 Cayenne S today. It's been sitting for a couple of days in the rain. Sure enough, I got the brake proportioning message and stuck in Park. This is the second time I've had this. This thread came to my rescue for the second time!! Again, lots of water under the carpet, and as with the first time the ground wire was the issue. I stripped and soldered it again, and I was on my way....Interestingly enough, I was on my way to fill sand bags in our town as we are in the midst of some serious flooding!!!

So again, thank you to all who have posted here!! You efforts and infromation have saved many a damp sole, and a sodden pig!!!

touareg

Interesting, so same wire you repaired before? Did you solder originally? Did it just corrode and fall apart?

I am going back into mine to do the one connection I skipped.

nelsonmx

Yes,it was the same wire as before. It is the brown to brown and black I believe to be a ground. The same issue as previous, there was green oxidation on the wire. I stripped them and soldered them as previous.....Last time I did all the crimped or whatever the original was by soldering and heat shrink. I'll go back when the weather dries out and recheck all the soldered joints just to be sure....I think this time I may solder and then cover each with a di-electric grease and heat shrink them to see if this provides more protection from the moisture that always seems to be there.

On that I'm not sure if the moisture accumulated was just condensation or from the drains being plugged. The truck sat for most of the winter and temperatures are up and down quite a bit. I'll report on the drains later.

MotoLimey

This *exactly* the problem I am experiencing... after sevearal weeks of a cold water leak into the foot well. I put this down to the aircon unit freezing in the Vegas heat but didnt put that much thought to it. The occasionally cold dribble onto my drivers foot wasnt something i was panicking about. Decided to leave it until the next time for a service #IamAnIdiot

This morning *boom it all went christmas lights -
Delighted to google it and find this thread... guess what I will be doing tomorrow




UPDATE NEXT DAY
It's fixed! It was exactly as described.... once I had lifted carpet I found it was wet (probably from leaking air con) and one of the wires had simply pulled apart at the join. I cleaned, rejoined and VOILA car is back to running normally again. Thanks for the excellent descriptive posting!!

Thanks all - /me buys the beers!

PorscheMonster

Spoke to soon...lights are back after 2 days of driving perfectly fine but now it's worst as now my radio and side view mirrors do not work... HELP please someone???

PorscheMonster

Double post somehow sorry