ohiobrits1

r553

What condition is your battery in? Do you have moisture under drivers side front carpet? There is main wiring harness under there which is subject to corrosion. The water can get in there from the cowl drains - have you ever cleaned them out?
a long shot is that the new control unit needs to be coded by dealer.
Good luck.

ohiobrits1

Thanks for the input. I will take a look under the carpet.

Battery is at 12.54V measured at the posts in the engine bay. A bit low, I'm guessing for an AGM about 12.8V would be fully charged. How low does it need to go to be an issue? The car has been sat for a few days in the garage at about 35F.

How do I check / clean the cowl drains?

As far as the Durametric goes I'm going to put a ticket in and see where we go from there. The cable has had issue with firmware updates (hanging) which may mean there is an issue there.

ohiobrits1

I located a tutorial on the cowl drains so don't worry about that...

ohiobrits1

Photo above - water under the trim on the drivers side, there was some pooling under the carpet. You can see the collection of grime suggesting this has been going on for a while. I have not attempted to look for the drains and clear yet.

Couple of updates.

Durametric - got it working (mostly) by running Windows directly in bootcamp. seems decently stable now. Couple of issues. When I do a quick test of faults it always hangs at the airbag stage? Any significance here? I am still seeing the loss of communication with the Door Control unit reported as before.

I looked into the battery some more and figured it was on the way out. I had less that 11.8V yesterday morning. Battery is now replaced and charged overnight. Sits at about 12.7V with no load and about 12.4V with the ignition on for diagnostics.

I did pull the carpet on the drivers side and it was very wet in the foam backing. I pulled it back and inspected the wiring channel, unwrapped the wiring loom and it looks OK. The only splices I can see are right at the top just before the wiring bundle disappears behind the dash underside. They are clear glue lined shrink wrapped and look in good shape internally from what I can see (shiny wiring). There are no splices in the lower level wiring that I can see. There is some taping on a bundle as it disappears under the seat mounting structure near the auxiliary fuse box on its way towards the sill. This appears to be just the start of the wrap for the run that goes to the drivers side rear door. There is some evidence of water this far along also. Im tempted to remove the rear carpet also and the seat mounting frame to get a better look.

I did some more checking of the door wiring by unwrapping the loom to understand what goes where and verified 12V at the Door Control module so the unit is getting power. The CAN wiring from the module is twisted white and white pair There is no white and white in the floor wiring so I'm struggling to understand next steps.

Below - Touareg schematic of the Comfort Can (http://www.volkspage.net/technik/ssp/ssp/SSP_298_d1.pdf). Shows conn to the drivers door directly from the central control unit. The passenger front and rear are working. The drivers side rear door window switch light is lit but I don't think the window works.


Any suggestions?

A wiring diagram of the convenience can would be very useful. Anyone know where I can get one?

ohiobrits1

Control unit locations. So why does my door control unit have a white and white can connection and there is no white and white in the floor wiring coming from the the convenience control unit....?
Locations of the various units from the Touareg doc: -

ohiobrits1

Splices right at the top on 2 of the lines, I'll need to check colors but this is probably the offending circuit.

I also located the CAN wiring diagrams. The twisted pair white at the door controller is shown which matches what I saw. Anyone know what the dotted white line means that connects the Can loop (red circle). The door control unit is on the right close to the red circle. I think I will try to trace the wiring from the Steering Column Switch module, there is likely a splice on that line from what I see, possibly the one Im seeing above.

Any tips on what to look for next?



A portion of the Computer Comms loop wiring diagram showing the door control unit to the right.

ohiobrits1

Update on the cause for anyone that may have a similar issue.

The issue is now resolved following a visit to Auto Assets in Powell OH (recommended for Porsche service if you are in the mid Ohio area). The problem was a worn door wiring harness. A couple of the wires had worn / broken at the door wiring harness to body interface inside the rubber boot. A new door wiring harness ($130) fixed the issue. This is a relatively easy fix since there is a plug at the door wiring harness to body interface which allows the door to be removed without disturbing the wiring. About 2 hours to do including removal of the door panel. If I had known there was a plug at that interface it would have been fairly easy to diagnose with a wiring diagram in hand (run a continuity check on each line).

Note that this is a 2014 with 60k miles so a somewhat surprising root cause.

The cause of water in the drivers side floor area is not yet diagnosed. The cowl drains were free of debris. I will check out the sunroof drains.

Eskimo1

Glad you got it diagnosed and repaired!

Gio_Hb

Any idea how to code it without the dealer?

gcarmigl

it supposed you can do it with PIWIS, but I have a copy of piwis and when I enter the option of “driver side door” there’s no unit control to work on. I’ve changed my driver door unit control but now the doors won’t lock when the car runs. Is the same symptom of a failure in the locking actuator , but I’ve already changed it 🤷🏻‍♂️

gcarmigl

Still can’t solve it