Battery Drain, Combination Comfort Databus in One-Wire Mode, 00470

[A5INKY]

Done lots of searching and reading on this and other forums and still wrestling with this issue.

Car is a 2006 Jetta TDI 5MT (MKV) with a bad battery drain issue. Started by charging and disconnecting the battery, will hold a charge for days disconnected from the car so the battery is fine. Then began with a VCDS scan that is showing only one pertinent DTC, 00470 Combination Comfort Databus in One Wire Mode. Measuring blocks show the CAN gateway will not go to sleep due to this assumed broken CAN wire somewhere. Following TSB 27_08_04 I checked the fuses and found fuse #15 for that module is pulling around 100mA after the door switch is fooled closed and the interior lights go out like normal. That one circuit is pulling way more than the >40mA the whole car should consume at rest. This makes sense considering the CAN gateway will no go to sleep.

Going with the most likely causes, the radio and driver door wiring harness, I first made note that neither had any DTCs set. Unplugging either will cause the CAN gateway to not see that controller (or radio) but will recognize them again as soon as plugged back in. Both are behaving normally and a physical inspection (as much as can be seen) of the harness to the driver door shows no damage to the wires in the normal breakage spot.

Before I post the VCDS Auto Scan results, I will ask if anyone can guide me on the next step for troubleshooting?

1. Is it possible to have a fault, say in the driver door, that is still recognized by the CAN gateway but has a broken wire or bad module? Perhaps I still have a broken wire buried in the driver door I just cannot see (old bellows style doesn't give much room to look) and the remaining single unbroken wire is enough for the door latch to report back to the CAN gateway?
2. Anyone see a central electronics control module go "bad"? Seems unlikely, just odd that every single module is reporting in fine but the DTC for one wire mode is still present.

Here is the scan results:

Chassis Type: 1K (1K0)
Scan: 01 02 03 08 09 15 16 17 19 25 42 44 46 52 56 62 72 7D

VIN: 3VWRT71K56M772309 Mileage: 213580km/132712miles

00-Steering Angle Sensor -- Status: OK 0000
01-Engine -- Status: OK 0000
02-Auto Trans -- Status: OK 0000
03-ABS Brakes -- Status: OK 0000
08-Auto HVAC -- Status: OK 0000
09-Cent. Elect. -- Status: OK 0000
15-Airbags -- Status: Malfunction 0010
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
19-CAN Gateway -- Status: Malfunction 0010
25-Immobilizer -- Status: OK 0000
42-Door Elect, Driver -- Status: OK 0000
44-Steering Assist -- Status: Malfunction 0010
46-Central Conv. -- Status: Malfunction 0010
52-Door Elect, Pass. -- Status: OK 0000
56-Radio -- Status: OK 0000
62-Door, Rear Left -- Status: OK 0000
72-Door, Rear Right -- Status: OK 0000
7D-Aux. Heat -- Status: OK 0000

-------------------------------------------------------------------------------
Address 01: Engine Labels: 038-906-016-BEW.lbl
Part No SW: 03G 906 016 AC HW: 028 101 223 9
Component: R4 1,9L EDC G000DG 7551
Revision: --H02--- Serial number: VWZ7Z0F3301482
Coding: 0050078
Shop #: WSC 00066 000 00000
VCID: 64CCA1B8A7BA063E1F5-8031

No fault code found.
Readiness: 0 0 0 0 1

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 02E-927-770.lbl
Part No SW: 02E 300 043 HW: 02E 927 770 AE
Component: GSG DSG 070 1126
Revision: 04507000 Serial number: 00000512070290
Coding: 0000020
Shop #: WSC 00066 000 00000
VCID: D1A2F86C48080396C43-8084

No fault code found.

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 1K0-907-379-MK60-F.lbl
Part No SW: 1K0 907 379 AA HW: 1K0 907 379 AA
Component: ESP FRONT MK60 0102
Revision: 00H13001
Coding: 0021122
Shop #: WSC 00066 000 00000
VCID: 71E2D8EC6848A396643-8024

No fault code found.

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 1K0-820-047.lbl
Part No: 1K0 820 047 EB
Component: Climatic PQ35 090 0505
Shop #: WSC 00000 000 00000
VCID: 68D4B5885B92625E33D-803D

No fault code found.

-------------------------------------------------------------------------------
Address 09: Cent. Elect. Labels: 3C0-937-049-23-M.lbl
Part No SW: 3C0 937 049 D HW: 3C0 937 049 D
Component: Bordnetz-SG H37 1002
Revision: 00H37000 Serial number: 00000000260671
Coding: 14010E234004180000140000001400000008730B5C
Shop #: WSC 05074 444 58638
VCID: 2A500F80851E904EE59-807F

Subsystem 1 - Part No: 1K1 955 119 C Labels: 1KX-955-119.CLB
Component: Wischer VW350 013 0402
Coding: 00063445
Shop #: WSC 05074

No fault code found.

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 1K0-909-605.lbl
Part No SW: 1K0 909 605 P HW: 1K0 909 605 P
Component: 39 AIRBAG VW8R 032 7900
Revision: 03032000 Serial number: 0038FD04236B
Coding: 0013113
Shop #: WSC 00066 000 00000
VCID: 397220CC70B82BD69C3-806C

Subsystem 1 - Part No: 1K0 959 339 E
Component: BF-Gewichtsens. 006 0005

Subsystem 2 - Serial number: 6332MSME0D3C666BS

Subsystem 3 - Serial number: 6342MSME0D6E072FT

Subsystem 4 - Serial number: 6351HSME091D44110

Subsystem 5 - Serial number: 6361HSME09144135

Subsystem 6 - Serial number: 63727SME086C4D036

Subsystem 7 - Serial number: 63827SME09064156Z

1 Fault Found:
01578 - Airbag Deactivation Warning Lamp; Passenger Side (K145)
009 - Open or Short to Ground - MIL ON

-------------------------------------------------------------------------------
Address 16: Steering wheel Labels: 1K0-953-549-MY8.lbl
Part No SW: 1K0 953 549 AH HW: 1K0 953 549 AH
Component: J0527 034 0070
Coding: 0010021
Shop #: WSC 00066 000 00000
VCID: 78F4E5C80B32F2DEA3D-802D

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 1K0-920-xxx-17.lbl
Part No: 1K0 920 952 L
Component: KOMBIINSTRUMENT 3HL 4312
Coding: 0023203
Shop #: WSC 05074 444 54671
VCID: 336E12E452D4D18656F-8066

No fault code found.

-------------------------------------------------------------------------------
Address 19: CAN Gateway Labels: 1K0-907-530-V1.clb
Part No SW: 1K0 907 530 F HW: 1K0 907 951
Component: Gateway H10 0120
Revision: H10 Serial number: 2800105C14A511
Coding: 3F3F0B40071002
Shop #: WSC 00066 000 00000
VCID: 2A500F80851E904EE59-807F

1 Fault Found:
00470 - Combination comfort Databus in Single Wire
012 - Electrical Fault in Circuit
Freeze Frame:
Fault Status: 01101100
Fault Priority: 3
Fault Frequency: 1
Reset counter: 74
Mileage: 213581 km
Time Indication: 0
Date: 2000.00.00
Time: 02:16:22


-------------------------------------------------------------------------------
Address 25: Immobilizer Labels: 1K0-920-xxx-25.clb
Part No: 1K0 920 952 L
Component: IMMO 3HL 4312
Shop #: WSC 00000 000 00000
VCID: 336E12E452D4D18656F-8066

No fault code found.

-------------------------------------------------------------------------------
Address 42: Door Elect, Driver Labels: 1K0-959-701-MIN2.lbl
Part No: 1K0 959 701 K
Component: Tuer-SG 024 2377
Coding: 0001269
Shop #: WSC 00066 000 00000
VCID: 36682BF041A6C4AE711-8063

No fault code found.

-------------------------------------------------------------------------------
Address 44: Steering Assist Labels: 1Kx-909-14x-44.clb
Part No: 1K1 909 144 K
Component: EPS_ZFLS Kl.5 D06 1701
Shop #: WSC 00000 000 00000
VCID: 336E12E452D4D18656F-8066

1 Fault Found:
00778 - Steering Angle Sensor (G85)
000 - -

-------------------------------------------------------------------------------
Address 46: Central Conv. Labels: 1K0-959-433-MIN.clb
Part No: 1K0 959 433 AF
Component: A_ KSG 0401
Coding: 137803087F09058F880F048051A0
Shop #: WSC 34340 001 1048576
VCID: 74ECD1F8175A96BE8F5-8021

Subsystem 1 - Component: Sounder n.mounted

Subsystem 2 - Component: NGS n.mounted

Subsystem 3 - Component: IRUE n.mounted

1 Fault Found:
00470 - Combination comfort Databus in Single Wire
012 - Electrical Fault in Circuit

-------------------------------------------------------------------------------
Address 52: Door Elect, Pass. Labels: 1K0-959-702-MIN2.lbl
Part No: 1K0 959 702 K
Component: Tuer-SG 024 2377
Coding: 0001269
Shop #: WSC 00066 000 00000
VCID: 377626F446AC3DA66A7-8062

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio Labels: 1K0-035-1xx-56.lbl
Part No SW: 1K0 035 180 D HW: 1K0 035 180 D
Component: Radio ZSW 016 0017
Revision: 00016000 Serial number: VWZ5Z7F6030627
Coding: 0040400
Shop #: WSC 00066 000 00000
VCID: 2142E8ACF8285316B43-8074

No fault code found.

-------------------------------------------------------------------------------
Address 62: Door, Rear Left Labels: 1K0-959-703-GEN2.lbl
Part No: 1K0 959 703 D
Component: Tuer-SG 021 2434
Coding: 0000144
Shop #: WSC 00066 000 00000
VCID: 316218ECA8C8E396243-8064

No fault code found.

-------------------------------------------------------------------------------
Address 72: Door, Rear Right Labels: 1K0-959-704-GEN2.lbl
Part No: 1K0 959 704 D
Component: Tuer-SG 021 2434
Coding: 0000144
Shop #: WSC 00066 000 00000
VCID: 326017E0ADCED88E5D9-8067

No fault code found.

-------------------------------------------------------------------------------
Address 7D: Aux. Heat Labels: 1K0-963-235.lbl
Part No SW: 1K0 963 235 E HW: 1K0 963 235 E
Component: PTC-Element 0404
Revision: 00800000 Serial number:
Shop #: WSC 00000 000 00000
VCID: 2D5A049CB4F0877600B-8078

No fault code found.

End ---------------------------------------------------------------------

I found a TSB for the airbag DTC, looks like a high connectivity resistance under the passenger seat that the TSB is guiding the tech to wire around the questionable connector. I don't see that causing this. The DTC for the steering angle sensor is likely from having had the battery disconnected. A recalibration once the issue is resolved should take care of that - again, thinking that is not going to pertain to the battery drain either.

Thanks in advance!

 

[A5INKY]

I should also add that I have not pulled the driver door skin to more closely inspect the wiring harness yet because the 00470 "CAN One-Wire Mode" DTC remains even after I unplug the driver door from the connector in the door jam. If it was a broken wire in the driver door area that DTC should go away when the door is unplugged.

 

[MyAvocation]

These aren't exactly as yours, but should provide some new ideas:

Infamous door harness: *http://forums.tdiclub.com/showthread.php?t=307719

Washer nozzle wires for this guy: *http://forums.vwvortex.com/showthre...70-Combination-comfort-Databus-in-Single-Wire

 

[A5INKY]

Shameless bump in hopes it will catch Oilhammer's eye.

 

[oilhammer]

I would be looking at that driver door harness. I'd also check for drains via voltage drop measuring across the fuses, per the TSB. I've found a lot of problems using that method on all kinds of cars, it really works well.

 

[A5INKY]

From what I have read, unplugging the driver door at the A pillar should restore two wire CAN communication, it doesn't, so I'm thinking that is not it. Also, no DTcs for the driver door, everything works great, and two wire comm not restored when unplugged. Also, as I said in the OP I did the voltage drop across the fuses test and the only outlier (never less than 100mA draw) was #15 powering the electronics control module.

Just seems like there should be a next step to this troubleshooting effort. I hate to just start tearing more of the interior apart if components and wire runs can be eliminated from the search through VCDS and deductive reasoning.

Any other tricks to finding faults like this?

 

[oilhammer]

Sorry, I should have read your post slower (I was just wanting to let you know I did see it, LOL).

Check the Central Convenience Module, behind the glove box. It should have two or three connectors, with some other slots unoccupied, IIRC. The CT suffix part has been superceeded to a DA, and these can cause some whacky stuff to happen.

18-pin connector, terminals 9 and 10, are the CAN hi and lo, you should be able to unplug that connector and see what your CAN bus mode does in the Gateway.

The Gateway itself is probably not the problem, but to narrow it down, you essentially have to disconnect everything on the CAN bus one by one and see what happens.

 

[A5INKY]

Excellent, thank you Oilhammer. That is just the next step I was looking for.

 

[A5INKY]

Bentley manual has been helpful, though for diagnosis it calls out for VAS 5051A tool which, of course, I don't have. Not sure if VCDS bridges the necessary tool gap or not. I also found a self study guide online that helped :

http://www.vaglinks.com/docs/vw/misc/vwusa.com_vw_mk5_jetta_electricalsystem_ssp_873403.pdf

I unplugged the CCM and the CAN in single wire mode DTC was still present. I opened the CAN module in VCDS and unplugged J519 electrical control system module and queried for a DTC in the CAN and no codes returned at all. Only thing is that the CAN module will not connect in VCDS with J519 unplugged (though it seems to stay connected after J519 CAN carrying connector is unplugged), so I am questioning if J519 is the actual cause of the fault.

My next thought is to make sure it is nothing else in the Convenience CAN bus related to J519 is at fault. My module unplugging and CAN gateway retest also included the Climate Control, Radio and each door module in turn even though they don't appear to relate to J519.

Not much seems to communicate via CAN or LIN as a slave module via J519. Since the DTC is related to CAN only, I'm thinking the LIN connected items cannot be the source of the issue. From the linked document, looks like just the wiper control, steering column, ABS and Data Bus OBD module are CAN connected to J519. This car has no Rain/Light Sensor. I unplugged each of the listed slave modules one at a time with the the one wire DTC persisting. Only module I could not test is J533 Data Bus OBD module as that causes a loss on communication with VCDS.

So right now I'm thinking J519 Electrical Control Module is the source of the issue. I can find nothing on the interwebs where this module has failed for anyone else. Between the total loss of any DTCs when tested and no apparent tendency for failure, I am not 100% certain of this diagnosis.

Ideas anyone? Oilhammer?

 

[Stutgart]

Pull J234, G85, J537. Does the Gateway and Can bus problem go away?

 

[A5INKY]

Pull J234, G85, J537. Does the Gateway and Can bus problem go away?

I didn't think to look to those controllers as none of them are part of the comfort third of the CAN system which is where my one-wire mode DTC is coming from. However if there is any possibility one of these controllers is the root cause then they are worth testing too.

Can you expand in the thinking behind your recommendation? I'm trying to learn as much about this system as possible. I'm sure this won't be the last time I'll be troubleshooting a CAN system.

 

[Stutgart]

There is a can bus problem, a steering problem, and an air bag problem. Those 3 modules eliminate the steering and the airbag. Hopefully the bus problem is with it too.

 

[A5INKY]

There is a can bus problem, a steering problem, and an air bag problem. Those 3 modules eliminate the steering and the airbag. Hopefully the bus problem is with it too.

G85 is integral with the steering column controller, so it has already been tested. I will investigate the airbag issue first thing tomorrow by unplugging it's controller and retesting. I had not focused on that DTC after finding it was a connectivity issue under the passenger seat that is well known enough to have resulted in a VW TSB. None of my research indicated it could result in a CAN system not going to sleep.

Generally though, it is always wise to fix the known issues first. Perhaps there will be some causal relationship after all. If that airbag controller doesn't end up being the cause of the single wire issue, I think J519 is going to get replaced.

 

[BuzzKen]

If that airbag controller doesn't end up being the cause of the single wire issue, I think J519 is going to get replaced.

Me has my money on this.

 

[A5INKY]

Darn, now I can now add the airbag module to the list of modules that disconnection didn't return the CAN system to two wire mode.

Found a J519 of the correct part number in the used part market. Going to replace it and hope that does the trick.

 

[A5INKY]

I hate it when interesting threads on challenging problems die out before resolution is reached. Not this time.

I replaced the J519 Central Electronics Control Module and the DTC for CAN system in one-wire mode is finally gone. Still have some buttoning up to do and retest sleep mode current draw, but I believe I found the root cause. I had scoured the interwebs using every logical search term I could conceive for this issue and found nothing, leading me to believe this is a truly rare failure.

Issues like this one make you want to pull your hair out, especially when you realize how little you make for the effort. Car had been to a dealer and at least one or two other independents for this battery draw issue before coming here. I learned more about diagnosing CAN/electrical issues than I thought I would ever need to. At least I got that out of it.

 

[BuzzKen]

Some may disagree with me, but in many cases, it's faster/cheaper/easier to just throw parts at it. Especially on older cars where parts are cheap and readily available.

But as you said, you just learned a lot.

 

[A5INKY]

Some may disagree with me, but in many cases, it's faster/cheaper/easier to just throw parts at it. Especially on older cars where parts are cheap and readily available...

That's debatable. I always seek a proper diagnosis before replacing parts, perhaps to a fault. I think it may be as a response to the overwhelming majority in car repair that change parts first then try to understand what went wrong second (or never). I am in awe of how many customers come in to my shop with issues that have had many expensive parts thrown at it by other mechanics with no resolution, yet speak cheerfully of the shop that took their money while failing to fix the car. I don't want to run a shop like that.

This CAN issue being internal to a control module (literally a "black box") not easily or conclusively tested is one of those cases where at some point parts changing is the only practical way. At least I understand the CAN system better now to more efficiently arrive at the correct part to change. This car could have easily (and needlessly) gotten a door harness, stereo, etc. had I not narrowed it down.

 

[oilhammer]

Glad you found it. Yes, CAN bus diagnostics without a dedicated "reader" can get cumbersome, because really ANY of the modules on the bus can cause the same problem.

The only way I know of to diagnose this is to one by one remove all the modules until all that is left is the Gateway.

I've replaced the CE module for various strangeness... refusal to work a certain output, etc. I've also replaced an SRS module for repeatedly and randomly firing off the unlock command to the CCM for no reason (thought the car was in an accident I guess). I've replaced a CCM recently because it decided to leave the left turn lamps on every time you locked the car (right side would flash normally, left side would just come on and stay on).

Just part of the modern automobile.

 

[A5INKY]

Thanks for your help Oilhammer. This was a good learning experience for me.

Just fired the car up after sitting two days with the battery connected. Now I know this battery draw issue is fixed for sure. It would drain the new VW battery the owner had just installed in just one night before. Good to go!

 

[James & Son]

What exactly does J519 do. Is it the main overall controller. Was it expensive.
Why could can bus not identify a fault caused by J519.

Edit; I guess I should be asking, does a can bus with one wire indicate a bad j519 fault or do you have to unplug the connectors as per your previous post #9 to know for sure.

 

[A5INKY]

James, nothing from either the ECU nor the CAN gateway pointed toward the Central Electronics Control Module (AKA J519). The code that came up in VCDS was merely letting me know something connected to the CAN system was causing communications to default to one wire instead of the twisted pair (2 wires) that system uses for normal communication. The link I posted in post #9 is a great resource for understanding the CAN bus system in our cars. Additionally, Wikipedia does a good job of describing just exactly what CAN bus is: https://en.wikipedia.org/wiki/CAN_bus

When the one-wire comm error is happening, the CAN system does not go to sleep and that creates a serious resting draw on the battery. I focused in on J519 because of the results of amp draw testing I did per a VW TSB that showed it was the source of the draw. But, as Oilhammer has said, the nature of the CAN bus system is that VCDS will only tell you of a fault, not what is causing it. Since J519 is responsible for load reduction duties among other things, it could have been a related CAN connected controller, relay issue or even a wiring issue that was manifesting as the draw from J519. At that point you have to start disconnecting controllers one by one until the error disappears in VCDS to find the root cause via process of elimination. Bummer is that the controllers are spread throughout the car and not easily accessed.

J519 is about $400 from the dealer. I found a used one for less than half that. Seems from the lack of troubleshooting info on the interwebs that J519 is a very low failure part. Therefore, I felt pretty good about getting one from the breakers.

 

[Stutgart]

A5inky, a big thanks for posting the CAN bus self study link. A better understanding is impossible without guidance.

 

[oilhammer]

CAN really sped up a lot of data transfer among controllers. Thanks again to Bosch, for making our cars (and now everyone else's cars) tick.

You know it was originally developed for factory automation? So factory machines could communicate with one another and keep the line running smoothly. When Mercedes-Benz came up with the W140 S-class in the early '90s, they needed something to handle all the ECUs in that car.... so Bosch came to the rescue. That's right, the top-of-the-line MB in 1991 used 5-year-old canning technology to make it work.

In school we hooked up lab scopes to the various data wires, and "watched" the transfer of packets (as best we could see... it is very fast). We locked a new Lexus SC430 up, and watched the CAN bus... took a full 10 min for it to finally stop its activity, and even then every few minutes it would show a little blip of something. Hit the unlock button and all sorts of data started bouncing around again.

 

[A5INKY]

The CAN Gateway has to distinguish between information packets from different controllers by the packets themselves. Seems there should be a way to electronically "see" which controller's info is compromised to help guide troubleshooting. I noticed my Bentley repair manual called out for VAS 5051A which it appears has been superseded several times and is now VAS 6150C. Does anyone know if this a tool can interpret that CAN data in such a way? I found this info on VAS 6150C HERE, but it doesn't specifically mention CAN diagnostics. I'm not about to run out and drop over $5K on this tool, just interested in learning what I am missing w/o it.

This car had been to the dealer and another supposed VAG trained independent already with no resolution before it came to me. Seems the dealer would have to have either VAS 6150C or something that can troubleshoot CAN systems. Maybe not?

 

[oilhammer]

That is just the newer wifi enabled scan tool.

What you are looking for is an actual CAN-bus testing device, like this:

http://industrial.softing.com/cn/pr...and-participant-oriented-error-searching.html

But that will only do a basic continuity test of the network, I don't think it can isolate a specific module as a problem spot.

Also, it won't "translate" a specific controller unless it knows the sender address (think MAC (Media Access Control) address on a LAN system).

I am not aware of any automaker that has this type of diagnostic stuff in the repair field, this is more reserved for the development side. But your request is one I think is valid, since I too have run into this same type of problem MANY times on MANY different kinds of cars.

As you probably know, the Germans are never very forthcoming with engineering level information, and since CAN is Bosch, this attitude trickles down to everyone now. You should hear what the Chrysler guy told us at ASE about Bosch and Cummins, LMAO....

 

[A5INKY]

That's not too surprising. Our disposable economy and increasingly wanting technical workforce has lead to an increasing level of modularity in car design. So many examples: DSG Mechtronic units that are only available complete, KKK turbos with no spare parts available and the list goes on and on.

We should be thankful on some level though. It is this new car repair reality that has given rise to the niche mechanic as previous service provider schemes are no longer effective. I'm not complaining.

 

[Wgr73]

Good info! (saved)

 

[JSWTDI09]

I have never tried it, but Auto-Polar has a CAN bus reader (sniffer) and logger that has been used by them to find and fix CAN bus communications issues. This post on their support forum has links to download their CAN sniffer and links to instructions for using it. I do not know how helpful this might be, but it might be worth checking out.
http://www.auto-polar.com/forum/showthread.php?272-PolarFIS-CAN-Reader-%28Sniffing-tool%29

Have Fun!

Don

{edit} I just looked at the instructions for this and it appears that it requires a Auto-Polar FIS, so this might not be what was needed for this issue. Oh well.