Transporter no comm

[scoper]

Help please!

T5 Transporter 2007. Crank no start. No EML on dash KOEO.
Codes set for ECU no comm by ABS, Gateway, IPK
Can talk to ECU on K-Line direct to DLC, no codes set, no engine bay activity and no fuel pump.
ECU has ( 4A load tested) powers and grounds - ECU is switching main relay,
Scoped full CAN activity at ECU plug.
Tested ECU on bench with just P+G = flat 2.5v on the CAN lines.
Got used ECU - tested on bench and have "awake and here" CAN activity. Cloned over original EEPROM, Int + Ext Flash.
Installed and ... Exactly the same fault. - This was second used ECU as first had no on bench CAN activity.

Re-checked, double checked and checked again. It has P+G+CAN comms, it puts out a 5v ref and signal ground, but nothing can talk to it.
I can go into it on live data but no data there
What am I missing ?

Friday,17,April,2026,18:10:31:34176
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 26.3.0.0 (x64)  HEX-V2 CB: 0.4701.4
Data version: 20260320 DS375.1
www.Ross-Tech.com

Dealer/Shop Name:

VIN: WV1ZZZ7HZ8H033490   License Plate:


Chassis Type: 7H (7J - VW Transporter Single/Double Cab (2003 > 2010))
Scan: 01 02 03 08 09 0B 15 16 17 18 19 1C 22 37 45 46 47 56 6E 76
          77 7D
 
VIN: WV1ZZZ7HZ8H033490   Mileage: 191800km-119178miles
-------------------------------------------------------------------------------
Address 01: Engine        Labels: 038-906-016-BRS.clb
   Part No SW: 038 906 016 AH    HW: 038 906 016 AH
   Component: R4 1,9L EDC         9712
   Shop #: WSC 00000 256 01574
   VCID: 5AED9FDA000721DAE17-5184
   VINID: 9E606AAAA1D8A886000C31090096A17A43

No Faults Found
  or DTCs not supported by controller
  or a communication error occurred

-------------------------------------------------------------------------------
Address 03: ABS Brakes        Labels:. 7H0-907-37x-ABS.clb
   Part No SW: 7H0 907 379 S    HW: 7H0 907 379 S
   Component: (M)ABS MK25E        0103
   Revision: 00H21001  
   Coding: 0000552
   Shop #: WSC 02736 790 00000
   VCID: 45D75CA699B9BE22BC5-5160

1 Fault Found:
01314 - Engine Control Module
            004 - No Signal/Communication
             Freeze Frame:
                    Fault Status: 01100100
                    Fault Priority: 2
                    Fault Frequency: 3
                    Reset counter: 15
                    Mileage: 191801 km
                    Time Indication: 0

             Freeze Frame:
                    Count: 128
                    Count: 8449
                    Count: 8194
                    Count: 0


-------------------------------------------------------------------------------
Address 09: Cent. Elect.        Labels:. 7H0-937-049.lbl
   Part No: 7H0 937 049 AB
   Component: BORDNETZ SGVER 1.0  1201
   Coding: 0000004
   Shop #: WSC 02736 790 00000
   VCID: 72BDD77AF8B7799AC97-5160

2 Faults Found:
01299 - Diagnostic Interface for Data Bus (J533)
            013 - Check DTC Memory
01341 - Control Module in Instrument Panel On Comfort CAN (J285)
            008 - Implausible Signal

-------------------------------------------------------------------------------
Address 15: Airbags        Labels: 6Q0-909-605-VW5.lbl
   Part No: 1C0 909 605 A
   Component: 3B AIRBAG VW51      0010
   Coding: 13122
   Shop #: WSC 02736
   VCID: 221DE73A6DD7A91AF97-5160

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 7Hx-920-xxx-17.lbl
   Part No: 7H0 920 952 B
   Component: KOMBI+WEGFAHRSP VDO V02
   Coding: 00413
   Shop #: WSC 00777
   VCID: 2C0109021F136F6A43B-5160
   WV1ZZZ7HZ8H033490     VWZ7Z0G5546428

2 Faults Found:
00562 - Sensor for Oil Level/Temperature (G266)
            30-00 - Open or Short to Plus
01314 - Engine Control Module
            49-00 - No Communications

-------------------------------------------------------------------------------
Address 19: CAN Gateway        Labels: 6N0-909-901-19.clb
   Part No: 6N0 909 901
   Component: Gateway K<->CAN    0001
   Coding: 00006
   Shop #: WSC 02736
   VCID: 70B9DD72F3BB4B8A3F3-5160

1 Fault Found:
01314 - Engine Control Module
            49-00 - No Communications

-------------------------------------------------------------------------------
Address 46: Central Conv.        Labels: 7H0-959-433.lbl
   Part No: 7H0 959 433 B
   Component: C11 Komfortgerát     0004
   Coding: 00021
   Shop #: WSC 02736
   VCID: 323D177A3D37399A097-4B1E

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio        Labels: 1K0-035-1xx-56.clb
   Part No SW: 7H0 035 152 H    HW: 7H0 035 152 H
   Component: Radio DE2           0007
   Revision: 00005000    Serial number: VWZ4Z4G4220809
   Coding: 0010200
   Shop #: WSC 02736 790 00000
   VCID: 270BF62E03F54C32AE9-5160

No fault code found.

End----------(Elapsed Time: 05:08, VBatt start/end: 12.1V/12.1V)-----------
------------------------------6 Faults Found-------------------------------

 

[Uwe]

This is indicative of something not happy with that ECU:

No Faults Found
  or DTCs not supported by controller
  or a communication error occurred

-Uwe-

 

[scoper]

I would expect the Central Electric module to flag a no comm with ECU as well. Just found out that apparently Cent elect was repaired right around the time the van quit. Can't see the connection unless it was replaced instead of repaired

Oh and 60ohms CAN H-L measured at the ECU

EDIT :
This fault :

Address 19: CAN Gateway Labels: 6N0-909-901-19.clb
Part No: 6N0 909 901
Component: Gateway K<->CAN 0001
Coding: 00006
Shop #: WSC 02736
VCID: 70B9DD72F3BB4B8A3F3-5160

1 Fault Found:
01314 - Engine Control Module
49-00 - No Communications

Is this definitely CAN comms or could it be K-line ? I tested for K-line signal at ECU but possibly not with the plug out.

 

[Dr Sheldon]

Tested ECU on bench with just P+G = flat 2.5v on the CAN lines.

Because it is looking for the Gateway maybe ??

Got used ECU - tested on bench and have "awake and here" CAN activity

Without a Gateway ??

Can talk to ECU on K-Line direct to DLC,

So Diagnostic communication to Engine ECU in this is K Line ??

Nothing is written clearly here ?


Put the original ECU in and do all your testing in the car - not on the bench !

What scope are you using ?

 

[scoper]

Yes Diagnostics is K-line

I would expect any module to give a CAN "I'm here- talk to me" signal - this was present every 2ms which is clearly different to the full CAN chatter I was getting with the ECU plugged into the car,.

ECU has ( 4A load tested) powers and grounds - ECU is switching main relay,

Scoped full CAN activity at ECU plug.

Re-checked, double checked and checked again. It has P+G+CAN comms, it puts out a 5v ref and signal ground, but nothing can talk to it.

Extensive testing was done on the car, sorry if that was not clear?
Additional testing was done on the bench as loss of CAN comms in these units is a common fault.

Not sure why it is relevant, but a Pico 4425a that I use every day.

 

[Vdub]

with this old cars and their problems you have to check things like main/fuelrelay etc first.
Does the glowpluglight come on when you turn on ignition?

 

[scoper]

This is indicative of something not happy with that ECU:

No Faults Found
  or DTCs not supported by controller
  or a communication error occurred

-Uwe-

Thanks Uwe, would I be correct in thinking that all this information :

Address 01: Engine Labels: 038-906-016-BRS.clb
Part No SW: 038 906 016 AH HW: 038 906 016 AH
Component: R4 1,9L EDC 9712
Shop #: WSC 00000 256 01574
VCID: 5AED9FDA000721DAE17-5184
VINID: 9E606AAAA1D8A886000C31090096A17A43

is being pulled off the ECU so it must have comms with it on the K-Line? Which from the WD everything else should have K-line comms too.

 

[Uwe]

it must have comms with it on the K-Line?

Yes, but not reliably, or at the very least, the ECU is not responding to the request for DTCs in the proper way.

-Uwe-

 

[scoper]

Any idea what would cause that - as it's had a (2 actually) replacement ECU? I am going to put the original data it came with back on the replacement in case it has had a Map that has corrupted and I've copied that across. Outside of that I can't think of anything.

 

[Dr Sheldon]

Not sure why it is relevant, but a Pico 4425a that I use every day.

It is relevant to me -

 

[Vdub]

Any idea what would cause that - as it's had a (2 actually) replacement ECU? I am going to put the original data it came with back on the replacement in case it has had a Map that has corrupted and I've copied that across. Outside of that I can't think of anything.

Why modify the maps on the ecu, make it stock with an FRF and see if it runs before ruining the maps..


best thing with this bus is unplug everything 5v related, so egr, maf etc, (even unplug camshaft- or crankshaftsensor, but not togehter)
This EDC ecu is known for 5v problems and try to crank, IF Crank- or Camshaft is unplugged starting takes a second or 10 before it will switch over to one sensor reading.

 

[scoper]

Why modify the maps on the ecu, make it stock with an FRF and see if it runs before ruining the maps..

In case the original ECU had corrupted data on it - that I then cloned to the used ECU, I am going to put the original data from the used ECU back on it. It will not start but if it is able to communicate then I will know the issue is the data.

This is a comms issue not fuel pump or sensors. The IPK has no comms with the ECU so it will obviously not start as it will be immobilised. I did check for 5v ref and it is there.

Whats an FRF ?

 

[Vdub]

data only gets corrupted if someone messes with it. Never saw an eeprom changed itselves..

 

[scoper]

Nope me either, alternative ideas welcome !

 

[Vdub]

you can attach any OEM ECU to the bus, without changing Immo, if the car starts and runs for a sec you know its good (shuts down after 1sec for incomplete IMMO)
Then use ODIS to (or maybe VCDS with correct IMMO-pin to) adapt IMMO to this ECU.

 

[Dr Sheldon]

If you have an Amp Clamp that can read milliAmps then, with your Pico, you can see direction of travel in your CAN and Kline wires - Confirm bidirectional communication. at that ECU !

Pico can also help you see what Modules are on line and sending / receiving messages on the networks.

 

[scoper]

you can attach any OEM ECU to the bus, without changing Immo, if the car starts and runs for a sec you know its good (shuts down after 1sec for incomplete IMMO)
Then use ODIS to (or maybe VCDS with correct IMMO-pin to) adapt IMMO to this ECU.

Yes that is my intention by putting the original files back on a used ECU. Didn't know if it was crank start die or just no crank so thanks for that. between VCDS, my IM508 and the Wiki I should be able to sort the immo.

If you have an Amp Clamp that can read milliAmps then, with your Pico, you can see direction of travel in your CAN and Kline wires - Confirm bidirectional communication. at that ECU !

Pico can also help you see what Modules are on line and sending / receiving messages on the networks.

Yep I have a Pico TA496 ( IMO the best Pico add-on) and did exactly that on the CAN when I first looked at it, and without getting too deep into it it looked like just one way comms to me. There was also plenty of network chatter going on at the ECU, that combined with the no comm fault codes along with all P+G being present led me to believe the ECU was faulty.
I am assuming K-line is working as I can connect and get ECU ID data as per scan above. However I am going to double check that as though the code descriptions say CAN I am wondering if they might mean/include K-line and the ECU data I have is coming via CAN from the gateway (IPK on this one)

 

[Dr Sheldon]

Just for clarity

Address 01: Engine Labels: 038-906-016-BRS.clb
Part No SW: 038 906 016 AH HW: 038 906 016 AH
Component: R4 1,9L EDC 9712
Shop #: WSC 00000 256 01574
VCID: 5AED9FDA000721DAE17-5184
VINID: 9E606AAAA1D8A886000C31090096A17A43

This tells us that the K Line is good ? Is there any other purpose for K line in that car ?

Are any modules not on K line for Diagnostics - Any on CAN and not KL ?

 

[scoper]

This is my question, does that tell me K-Line is good ? I do not know if there is another purpose for it.

Central Elect is not on K-Line, only on Comfort CAN so diag is via IPK

SRS is on the HS-CAN, but not on K-Line AND it is not setting a missing ECU comms fault.

On VCDS code descriptions do not say CAN comms, just comms.

 

[Dr Sheldon]

IPK

What is IPK ? Instruments ?