When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I had the exact same problem and I followed Touareg's instructions and my P!g is now back among the living.
The moral of the story is to clean out those drain plugs!
Glad to hear it helped someone!
Did you get stuck in parking lot like me and spent 1 hour trying to figure out how to get the stick out of park
Did you have the same wires have the same issues? My black wire had a good clean solder, so I left it, but now wondering if I still missed something.
I suspect this car has been wet before, as that amount of copper breakdown takes a while. Not sure where the PSM module is, but going to start researching.
So, I ordered relay 443 under the driver's seat, after reading a bit what it does. My understanding is it is used to trigger power to the rest of the CAN modules, when the car is powered on to run it. One of the repaired wires is what runs to the relay, and triggers it. Pretty sure you can see it in the attached picture.
One of the things I noticed a few years ago, is if I plugged in a bluetooth scanner, it appeared to draw too much power and made the car run in a bogged down mode, and erratic. Pulling the module instantly restored power. I would then read codes and a lot of modules had communication errors. I chalked it up to cheap 8 dollar ebay ELM OBD module and just used it to read codes, and reset.
After doing the bundle wire repair, I thought that may be what caused the issue with that module for OBD, so I tried driving with the module again, but same deal.
Now I replaced module 433 under the seat, cleared my code for the Throttle control I keep getting, and also the Coolant Sensor, both say intermittent signal.
Left the module in, and now car drives fine, car seems to boost better, and now I wonder if the relay was just worn and not making good contact, causing more resistance in the circuit. Typically it would throw the two CEL codes right away, after quick 5 min drive, no codes.
Too early to tell but we'll see if I still continue to get codes. Would be nice if this is a cheap 35$ fix, as this seems to be like the 993 and the 944/968 DME relay sort of deal, a constantly energized relay that wears over time, carries a lot of current, and is critical for the car.
I have in the 50k mile range and 2009 model, so age was a factor more than miles, but still not 100% this re-solves the last of my problems.
I started with the fuse box on the right dash, as I mentioned, the bottom two rows of fuses were getting no power. I disassembled the dash and fuse box and identified the power lined feeding these rows, there were three power lines. Following them back into the thick harness that runs from the fuse box then under the carpet passenger side, I found that all three are actually spliced together to form a single power line within the wrapped harness.
Following this single power line, it ran back up and into the upper dash, along to the driver side of the car, down and under the carpet to a relay (the only one) mounted right beside the battery. At that point I tested the power and ground going into the relay, and also disassembled the relay itself and tested it. Power and ground were fine, but the relay was not tripping and providing power to the systems upon ignition.
So next step was to test the power used to engage the solenoid and complete the connection. Power was fine, ground was not. I followed this small ground back up the harness and at a position roughly where your left foot rests, there was a series of spliced connections for a number of wires (again, within the wrapped harness). That was exactly where I located that this wire was spliced, and had corroded and came apart. I cleaned the wired, soldered and wrapped, and all systems are perfect.
In the same location, there were a number of spliced connections, I inspected all of them and found another getting close to failure, so it was repaired in the same way. Then I resealed everything, and have no problems.
To hopefully assist anyone with a similar electrical issue, pictures are attached: battery shows where the relay is that powers the systems (top right, relay removed, purple), harness shows the stripped wiring under the carpet, broken shows the connection as I found it.
Ultimately, I believe it was moisture and salt that corroded the connection, although it looked poorly done in the first place.
And if anyone wonders what that wire I soldered probably was, it goes to power the Driver Identification Control Unit, it too is on the CAN DRIVE Bus as well as the regular bus.
Not sure what it does, anyone? It has a Diagnosis line, whatever that means.
The relay 433 I replaced, was the relay that goes to this unit too.
Glad to hear it helped someone! Did you get stuck in parking lot like me and spent 1 hour trying to figure out how to get the stick out of park Did you have the same wires have the same issues? My black wire had a good clean solder, so I left it, but now wondering if I still missed something.
I was parked at my house, got in to go to work, got the codes and, because I keep an eye on this forum, I knew immediately what it was. I have plenty of cars around, so I drove a spare until the weather improved and I could get the floor dried out. When I pulled up the rubber mat and the carpet, the footwell was literally full of water to the level of the door frame. This all happened in spring, so we had several inches of late spring snow that was melting in the sun and then freezing solid overnight.
On the next warm day, I got the drain plug out, dried out the footwell as best I could with towels, cracked the sunroof and set a fan blowing through the footwell to encourage evaporation. The next day it was dry enough to do the wire fix.
It was exactly as you described it, although I seem to remember that I redid three wires, so I must have don the black wire as well. I didn't solder, though. I did a serious twist, thoroughly wrapped the joint in electrical tape, then put on heat-shrink tubing. The cloth bundle wrap had come apart, so I wrapped the entire bundle in thin bubble wrap, zip tied it together and stuffed it back into the plastic channel.
The whole operation took maybe two hours, and overall it was easy and fun to do.