Electronic damage from water leakage - cruise control & keyfob don't work - help!

Hello!

I am new to posting in these forums, although I have been a long-time lurker. Lots of great info on here, and extraordinarily knowledgeable people! I’m hoping for some help to my recent issue. I have a 2010 Jetta TDI. I absolutely love my car and so I’ve opted for the emissions modification instead of the buyback – I want to keep my TDI!

Backstory:

I suffered from the common leaky-sunroof problem during a heavy rain last month. Driver’s side footwells front and back were filled with water (car was on a slant). Insurance company had me take it to the dealer to get the leak fixed (driver’s side sunroof drainage tube), I got the car well cleaned, and then while the car was at the cleaner, it started having electronic problems (headlight not turning off, various dashboard warnings on all the time, etc).

New Problem:

Insurance had me take it back to the dealer, where they replaced the control module. Seemed to fix most problems, however, now I have three new problems:

1) The car does not respond to the key fob. I have both key fobs, and while the red light works on them, the car doesn’t respond. Can’t lock/unlock, can’t pop trunk, panic button, etc.
2) The cruise control doesn’t work. When I am in motion, the odometer reading is replaced by this warning sign: "! and Cruise Control symbol" (picture below - may need to right-click "open in new window" because I'm not sure I attached it correctly).

3) Suddenly the tire-pressure monitor is on, even though my tires are full (and nearly brand new!).

Question:

I am terrified of taking it back to the dealer because the insurance company basically told me that any additional repairs (they’ve already spent $2,500 on this claim) would result in a total loss. Since at this point, TDI’s are basically irreplaceable, I’m trying to avoid a total loss.
Any ideas on what the problem and solution might be? I would really like to be able to discuss this issue with the mechanic at the dealer on Wednesday with some suggestions. My understanding was their next move was going to be replacing the fuse box, but that would trigger a total loss. I'm hoping the actual problem might be something more simple (programming, or loose connections?)

Thanks for your help!

i'd total it; they'll be chasing electrical gremlins till you're bankrupt. i know nothing of the newish cars, are these serial communication cars? why would they replace the fuse box? it doesn't seem like a wise move, more of a money grab since they see they have the insurance company footing the bill.

also, how is the insurance company covering this... it wasn't a flood, it's lack of care by you. I can't understand why insurance is involved. who is your insurance company; next time I need tires I'd like to give them a call, see if they wanna cover that.

Hello! Thanks for the reply. I have comprehensive insurance coverage through Geico. They did not pay for the leak repair, that was on me ($170). However, they pay for the flooding repair and any electrical damage (so far it's been about $1,800, plus the $800 rental car provided by Geico). You should look into it - super cheap to add on to a policy (about $40 every 6 months) but covers you for everything! I'm not sure what you mean by "it's not a flood, it's lack of care by you", but whatever.

I'm curious to know if anyone has seen this issue before, as it's not hard to find a lot of people that had their cars flooded due to leaky sunroof drainage tubes (it seems to be a common problem with Jettas and Passats). I'm hoping to not total it, because I love my Jetta TDI and it's irreplaceable (you can't buy them because of the emissions scandal).

Also, I discovered a fourth problem yesterday:

4) My lock button does not work. I do not have the ability to lock my car!

I would look at the buyback and walk away from it. It sounds like you might have gotten water behind the dash and, unless you can totally dry it out, you will continue to have problems as things corrode due to the moisture. maybe you can still pick up a new 2015.

All of your issues point to a faulty CECM which should be above the pedals on Jetta of the year you have.

Spending $1800 for this issue is nonsense. I'll take your car and I'm pretty sure I'd be able to fix it for ~$180, 10 times cheaper.

If the CECM was replaced with brand new, it is possible that a) incompatible CECM was installed b) it was not programmed properly c) both.

What I personally would do in this case? Well...

I have a little bit of skills holding soldering iron in my hands. Firstly, I'd try to pull the damaged CECM, pop the cover and inspect/replace the burnt components.

If no go, then I would visit local salvage yards and pick up a compatible CECM, a pair of keys belonging to that car (yes, even in salvage yards you can find a full set of keys sometimes), ignition cylinder and door lock cylinder.
I'd swap all of that. If it works but you only managed to get one key, I'd go to a specialized shop and ask a spare key to be cut and adapted.

My 3rd option (the last one) would be the dealer. This options is the most expensive and very often dealers are not very skillful nor knowledgeable.

Everyone in the forums will be pushing to get rid of the car (either total it, or buyback option). I do understand what does it mean a love for a car. Sometimes you just love it too much.

Post your full autoscan with VCDS here. It would be very useful if you could find some older autoscans of the same car prior to any repairs.

Henrick,

Thanks for the info. The dealer completely replaced the CECM, I presume with a new module. So I'm wondering if they messed up the re-install process. Does the CECM control all of the below?
1) the key fob (lock, unlock, pop trunk, panic)
2) the cruise control
3) the TPS warning light
4) the power door lock

If so, then I definitely think it could be an incompatible / defective / miswired CECM. I'll look around online and see if I can't find the compatible CECM and some documentation. Since my insurance is covering it, I probably don't need to pick through junked cars for a compatible CECM - it sounds like the dealership messed up.

User kjclow above said something about "water behind the dash". I don't think I did get any there water was only on the floor. But if water did get back there, are there any electronic components back there, or is it just the screen that displays information?

Thanks so much for your help!

Why don't you just go back to the dealer and have them warranty/fix the problem? Or has it been a lot longer since the module was replaced than you dialog would lead us to believe?

Tadawson,

I will be taking it back to the dealer on Wednesday - they only finished the work last Friday. But I'm trying to learn a little more about the problem, so if the dealership tries to say "well we have to do this and that", I can respond with some educated notions. Any work that is new, and not just fixing what they've already done, would total the car.

So are you thinking Henrick might be right, and the control module was simply not compatible / wired incorrectly / defective? That would be the best case scenario because they would have to fix it, and I'd get to keep my car!

Thanks for the reply!

All that stuff sounds common to that module, and with a CAN bus car, it's pretty much all or nothing if a module is communicating or not. I was not clear reading if this stuff never worked when you got it back, or died shortly thereafter. Never points to coding, and died shortly thereafter points to a bad part, at least as I see it.

It's always good to know as much as you can . . . my concern was that you might be paying for what should already be covered.

Jeffro420 said:

Henrick,

Thanks for the info. The dealer completely replaced the CECM, I presume with a new module. So I'm wondering if they messed up the re-install process. Does the CECM control all of the below?
1) the key fob (lock, unlock, pop trunk, panic)
2) the cruise control
3) the TPS warning light
4) the power door lock

If so, then I definitely think it could be an incompatible / defective / miswired CECM. I'll look around online and see if I can't find the compatible CECM and some documentation. Since my insurance is covering it, I probably don't need to pick through junked cars for a compatible CECM - it sounds like the dealership messed up.

User kjclow above said something about "water behind the dash". I don't think I did get any there water was only on the floor. But if water did get back there, are there any electronic components back there, or is it just the screen that displays information?

Thanks so much for your help!

Click to expand...

Take it to the dealer to perform warranty work on the installation which they completed incorrectly.

As for CECM controlling the things you mentioned:

1) Keyfobs and communication between them and the car. Yes, it controls that
2) No, cruise should not be directly controlled by it but the cruise might need some information from CECM which it isn't providing
3) TPMS light. Does you car have ABS-based TPMS or are there any wheel sensors installed? If it uses wheel sensors, then CECM might be responsible, I'm not 100% sure
4) yes for power door lock.

Would be intereseting to see VCDS scan of the car. There should be plenty of fault codes giving at least a hint on where to start looking.

I wish you the best luck of sorting the electrical gremlin.

On the 2010 the tmps are wheel sensors. They may need new batteries and this is coincidental.

Sunroof

One of my MK5s leaked down the A pillar to the footwell. When I had the fused cover off, it was leaking water into the fuse box itself. I had a few electrical connection issues where the fuse was good, but the contacts were heavily oxidized. I used Dexoit on all of the connections and it solved my problem. One of my other MK5s is a insurance writeoff for water damage (minor - barely breached the door sill). I pulled carpet - padding and cleaned all of the electrical connectors with Deoxit. The car been trouble free for over a year.

Obviously, things can vary as far as electrical goes. I would try picking up a can and spraying the connectors.As mentioned by Herrick, I would also get the stealership to take a look at the module again. A VCDS scan would also point to issues as well. Worst case, go for the buy back and pick up a MK5 BRM. They are great, once you get a handle on the common wear items (DMF - Cam - Door harness)

Good luck!

tadawson said:

I was not clear reading if this stuff never worked when you got it back, or died shortly thereafter. Never points to coding, and died shortly thereafter points to a bad part, at least as I see it.

It's always good to know as much as you can . . . my concern was that you might be paying for what should already be covered.

Click to expand...

Hey tadawson! Thanks for the reply, and yes I realize now that I could have put more info in the initial post. To clarify:

All of these items worked well before the water damage - no electronic problems at all. However, as soon as I picked up the car from the dealership, all of these problems were evident (although I did not notice the lack of the ability to lock the car until later, I believe it was present all along).

The reason I did not simply leave the car with the dealer when I picked it up Friday was because the mechanic who did the work was out until Wednesday (tomorrow), and I had to return the rental per Geico. So I have an appointment Wednesday with the mechanic and my insurance agent.

It sounds like they may have put in a bad part or wired it wrong - I am going to do some research on the control module and see if I can find any information or documentation pertaining to its setup. Any resources you may have to point me in the right direction would help!

Thanks again,

Jeff

kbaisley,

Thanks for the reply! So my insurance paid for a car detailer to rip out the entire bottom carpet, thoroughly dry and clean, to remove all water damage. While they were in there they found some corrosion in the fuse box connections and cleaned those out - although I don't know the exact product they used. It was like $850 so I am super glad I have comprehensive coverage through Geico!

kjclow, thanks. I'll ask them to look at the batteries for the TPMS while they poke around the module.

Henrick, thank you so much for the breakdown. I will request a VCDS scan to find out what error codes might be popping up. I've had the infamous
P0401 error code for some time, so I'm kind of used to the check engine light being on, but it may be that some other error codes are now appearing. My hope is that the "stealership" (haha, great name) can fix their mistake and get the 4 electronic problems working again.

As for the type of TPMS I have, I checked the valve stems and they are metal (not rubber). I believe that implies that I have a direct sensor, not ABS-based. So that lends credence to the theory that the error may be CECM based.

Crossing my fingers that my visit to the stealership tomorrow will resolve all these gremlins in one fell swoop (I'm imagining a dangling, unconnected wiring harness). But if it doesn't, I may end up taking the buyback and searching for something else. It's just difficult to shop around, because no gasoline powered car is going to get the MPG my TDI does, and no hybrid / electric car is going to have the OOMPH my TDI does (and I can't afford a Tesla yet )

Thanks everyone for the help with these issues! I will post a follow-up after my dealership visit tomorrow, so that anyone searching for this type of issue in the future can know what happened.

Also, from the dealership receipt, looks like they installed CECM part number 5K0-937-087-G-Z7A. I can't find this part number listed at My-GTI, so I'm wondering where this came from? I'm having a hard time finding out exactly which CECM is supposed to go into my Jetta TDI (from what I've found on this forum, it is a MK6 MSFW with a highline full MFD+ display).

If the TPMS is in the valve stem, there is no way to replace the batteries in each unit without pulling the tire off the rim. Well, ok, the tire doesn't have to come off but the sensor is on the inside of the valve stem.

Hey all!

First of all, I wanted to thank everyone who gave me some feedback - you guys are great here at TDI Club Forums!

Second, I wanted to update everyone on what happened. So, after taking my car back to the dealership, I spoke with the mechanic directly about the programming done on the CECM (much more knowledgeable than the representative). The following problems were caused by:

1) The car does not respond to the key fob. I have both key fobs, and while the red light works on them, the car doesn’t respond. Can’t lock/unlock, can’t pop trunk, panic button, etc.
[SOLVED] The keyfobs were not properly programmed to match the new CECM. Once this was completed, the keyfobs now work perfectly!

2) The cruise control doesn’t work. When I am in motion, the odometer reading is replaced by this warning sign: "! and Cruise Control symbol" (picture below - may need to right-click "open in new window" because I'm not sure I attached it correctly).
[SOLVED] Apparently this was an issue with a control module within the steering column. They replaced that and it works fine now. I believe it is called the "Multifunction Control Module", and tends to convenience things like power door locks (#4) and cruise control.

3) Suddenly the tire-pressure monitor is on, even though my tires are full (and nearly brand new!).
[SOLVED] This was a CECM programming issue, not batteries in the TPMS!

4) Door lock button does not work
[SOLVED] This was fixed when the steering column control module was replaced (same as solution to #2)

So, at this point everything is fixed and the car runs beautifully. I realize sometimes electrical gremlins can continue to pop up. My intention is to keep the car for now, and if anything electrical goes wrong prior to September 2018 (when the emissions modification is released), I will change my offer to buyback.

Thanks again for all the help guys! Have a great day.

It's amazing that all those things would have been fixed had the dealer just completed the original job.

Yep, as expected, all the issues are related to CECM.