If it got water in it, it's probably fried. Get the part number off the device and find one at a salvage yard, and install that. Make sure the connectors on the harness aren't corroded.

 

Did the dealer find water / moisture under the passenger side carpet or in the TCM box? Also, I seem to recall that someone had a bad ground somewhere around the a-pillar area under the dash that caused TCM issues.

If the transmission runs normal for a few minutes, I question whether it's the TCM because the TCM is controlling the transmission during that time its running normally. Call the dealer back and ask them for the diagnostic codes for the TCM or if you have access to a VAG-COM scan the TCM for faults. Again, I really question whether the module is bad.

If the TCM cannot rationalize an input, it will interrupt 12 volts to the tranny and the tranny will run in emergency mode (aka safe mode) so as not to damage the transmission. So, it could be an input that doesn't make sense because of wiring/corroded connection issues or bad sensor.

The TCM is easy to replace but you may need a VAG-COM to code it properly. e-bay might be a good place to pick up a used one. There is an on-line used parts site (don't remember the name) where others have bought used electronic modules.

 

Thanks for the information guys!

First, I got the part number (3bo-927-156-aa , not sure if the o is actually a zero?) from the dealer ($90 to diagnose the error), I'm going to research it after class today. I think my mechanic can install a new one for me I just gotta make sure he has a VAG-COM.

In new news on my trip back from the dealer yesterday the car switched between emergency and normal mode probably 6 times in the 10 minutes, but on my way home from class it stayed in emergency mode the whole time.

I checked under the passenger seat, and at first I didn't find any water. But as I dug deeper things started to get moist, and right at the TCM I would guess the padding was at 33% water capacity. I have class all day today (whihoo), so I won't be home to take a closer look and dry the thing out until late.

I'm really hoping your right kenblasko, I would think that since it works intermittently that it's some sort of connection problem. The original code I got from the auto store was P0600, I'm not sure if the dealer got any newer codes than that.

I gotta run now but I'll check back throughout the day and update tomorrow, thanks again!

 

The "o" is a zero. P0600 is a data bus error. The TCM communicates with the ECM for data. If critical data is missing, the TCM will operate the tranny in emergency running mode. I really don't know how the dealer could diagnose a bad TCM without first drying everything out.

Open the TCM box up and make sure it's dry inside. Throughly dry everything. Clean the TCM connector. Follow the harness back to the front and look for grounds that might be corroded. You should open up the wiring harness since I believe there are internal ground splices in the harness. The harness should go back to connectors in the right a-pillar area. There should also be a ground connection at the lower part of the right a-pillar area. Make sure that is not corroded.

Also, you need to find the source of water ingress. Search for water ingress and read. Here's one thread. http://www.passatworld.com/forums/showthread.php?t=230249

 

Great news, I dried the car with a space heater and fan for over 6 hours today, and just drove 35 minutes without going into emergency mode! Tomorrow I'm going to call the dealer and complain and try to get my $90 back. There is still a check engine light on so I guess I'll find out what the code says before I call.

Thanks for the info on the water ingress and wiring, I'll check that out tomorrow when I wake up.

On a separate note, I had them align the car but it still veers to the right just as much before. What else can I check, or should I complain about that too? The did check the tire pressure at the shop and it's correct.

 

Good news on the TCM. I agree on getting your $ back. My guess is that the dealer never pulled the carpet up.

Have them redo the alignment. Do you have the before and after alignment sheets for comparison? Ask to see them. Seeing how they obviously didn't check for water, they probably forgot to do the alignment.

Yes, get the codes. If you don't know already, Autozone will read the codes for free. Write the Pxxxx codes down.

 

I called the dealership and was told that if it has any water on it that it really is broke and I still need a new one. I have to take my car in Tuesday to check out the alignment again, so if the car is still running fine I'm going to press the issue and ask to talk to a manager if they won't give me a refund, and if that doesn't work there is always the credit card company. The check engine light is off and the car is running just fine.

I just checked all those water leak links and I was amazed of how much crap was under my hood. I think I could have grown a plant with all the dirt in there. The pollen filter was disgusting so I cleaned it out, and unclogged the two holes, so hopefully that will stop the water ingress. To my surprise the sunroof drains were working just fine.

After checking under the carpet again, I noticed the water was coming from the rear passenger seat (today the front was dry and the back was starting to get moist again). How is water most likely to make it there?

Thanks,
Jake

 

clear out the drains underneath the battery and behind brake master cylinder. if it rains hard, the water builds up and flows into the intake of the air conditioning and flows through the "pipes" that bring ac/ heat to the back passengers. its the black metal opening underneath the seats.

 

Thats definitely it Dominick, right underneath those black pipes there was standing water. I have two towels, a space heater, and fan drying it out right now.

I cleared out two drains, one under the battery and one about a foot away from it. Was that the one next to the master cylinder? I'm not sure what/where the master cylinder is, so I could have missed that drain.

 

well i heard some cars have one behind the brake master cylinder and some dont, im not 100% sure about that though. the brake master cylinder is that (usually) black circular piece of metal on the driver side of the fender wall. its right behind the brake fluid resevoir

 

another thing to watch out for is the gasket for the ecu box. water leaked in there for me and fried my ccm. i had standing water about an inch high in my driver feet area as well as the back

 

Have you been using your a/c? After running your a/c for a while, leave it running and park it for a while and then check underneath the car on the ground towards the passenger side and the back firewall to see if the water is draining from the evaporator drain.

You still might want to remove the glove box and then the drain funnel and clear any debri from the drain. Others have found a slimy mess there. If that gets plugged I wouldn't doubt if water might drain through the HVAC duct to the rear passenger area. http://www.passatworld.com/forums/showthread.php?t=265009&highlight=drain+funnel
http://www.passatworld.com/forums/showthread.php?t=245517&highlight=drain+funnel

 

Thanks for the AC info! I'm away all weekend so I won't be able to check for several days but I'll check when I get back home

 

Just got back from the shop, they refunded half of my diagnosis fee. When I turn off my car there is water dripping from underneath the front passenger seat, so that part at least that isn't clogged. Everything seems to be drying out more, I'll keep an eye on it though.

Thanks again for everyones help

 

I'm having the same type of error. I have not been under the passenger carpet, but under the driver's side where I found no water but a black box. From this post that references the passenger side, I'm thinking that that box wasn't the TCM. We're not discussing a RHD car are we?

I've been to relative's transmission shop where his test said 'range error'. The supposedly responsible part was replaced but the error can't be cleared. Sorry, which part, I don't know as I was at work.

So which side is the TCM on, and is there some general scan tool process that might do sort of a 'blast reset' to put the TCM to some initial start state? I ask the last part because in working on the 'possible leak site' the battery has been removed. It seems that the problem would reset itself and come back some other day before the battery was removed. Either that or the bug is now rock solid.

My main source of water has been the rear door inner panel seals. Though the pollen filter gasket was damaged, there seems no evidence of water in front well. I'm going to go back out later and pull right front side carpet and check it out for sure.

I removed front seat on the left side to check there . Do I really have to do that to get to the right place on the passenger side?

Thanks,
davnport

 

The TCM is on the right passenger side. When I was getting the error I couldn't reset the code (well I could, but it came right back within one second). I never had to remove my seat to soak up the water, but it certainly would have made things easier if the seat wasn't there (I'm not sure how much work it is to remove so I didn't even bother trying)

 

I pulled up the carpet, pulled out the black box and dumped the water out. There was about an inch of standing water in the floor depression. It's undergoing some forced-air therapy right now!

After I got the TCM and the connector reasonably dry, I reconnected it and drove the half-block to the shop and, after a couple of attempts, was able to successfully reset the CEL and get only one gear indicator at a time to light. It's back in my garage under the fan to really get the carpet dry.

Apparently when the pollen filter housing leaks, the water never gets on the top of the carpet, but runs down the firewall into the spongey stuff under the carpet. Top of the mat never has felt wet. I have made the area around the filter base watertight and sealed the cowl at the bottom of the windshield so maybe I'm out of the woods. Fingers crossed!!

 

That's good news for your car. I still can't seem to find my leak after I checked all of the known places, so when I get back home tonight I'm going to grab a hose and try again. It's been raining pretty hard and the foam under my seats are starting to get wet yet again, so I can't just ignore this one

 

2002 has a p9 recall for the pollen filter did they not, I would get that done see if it stops your leak. The TCM is really easy yo get at, just lift the passangers side carpet and its in the black box. If you need one let me know.

 

I got flooded here in Indiana and had to do the work myself (bullheadedness) and the TCM was $220 from car-parts.com and I went ahead and licensed my Ross-Tech software for $249 with cable and updates.