Fried something in CAN bus. Kicking myself...

Trevor801

Member
Joined
Dec 5, 2016
Location
Nc
TDI
04 golf 12 sportwagen
So after successfully completing a 5 speed swap on my 04 bew golf I started on the wiring. Being in too much of a rush I "accidentally" sent 12v down the orange and black CAN high wire at the tcu harness. No more start....
No glow plug light, no cell, just turns over and over. I have it at a shop right now they have tried a second ecu and cluster. They are able to communicate with all modules but say they are not communicating with each other. The 109 relay seems to be fine, so I'm pretty sure I fried at least one module in the CAN network. I'm going to the shop tomorrow and will try to post a full scan. They want to put the load reduction relay 175 back to stock instead of the 53 I have in there now for safety switch and the other wires I cut for reverse and speed. Sorry so long, was hoping someone would have some insight other than the obvious huge mistake I made... Would like to have a working car after putting all the time and money so far.
 

sawmilldon

Veteran Member
Joined
Sep 19, 2016
Location
WA
TDI
2004 Wagon
I just spent some time looking at the CAN on my 2004 BEW Wagon.

Do you have Vag Com? If so, you should know pretty quick if there is activity on the system.
 

wonneber

Top Post Dawg
Joined
Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
Long shot.
Did anyone check the fuses?
Do all the dash lights com on with the key?
 

tgray

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Sep 12, 2004
Location
Marengo, IL
TDI
'02 Beetle, '05 Golf, 2000 Jetta, 2001 Jetta, 2002 Jetta
There is another piece to the puzzle you need to consider. I had a lot of problems with my swap from a gas to tdi and found the comfort module was not compatible with the older swap stuff. Lack of communication can mean something is taking the communication down like a short to ground. You could have fried something like your comfort module and it takes the signal down to the ground. Try unplugging your comfort module and see if the ecu comes to life. I would get a wire diagram and trace every path of the can bus out and see what it feeds. Usually in a case of sending voltage down a wrong path like you did will fry something out. It could be a wire or module but most likely a module if you don't smell any burning. With the ecu and the cluster swapped I would look at anything else in the path. I sparked 12 volts to a Passat gasser can bus and fried the throttle position sensor out. If you don't have a good wire diagram just try unhooking everything you can but still leaving the ecu and cluster and the test port connected. verify communication and see if that will fire everything off. In these can bus cars there are end points for the can bus in the window motor computers.
 
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derek5120

Veteran Member
Joined
Sep 25, 2014
Location
Arthur Ont.
TDI
2003 jetta GLS
Very first thing to do is check pin 6 to 14 in your dlc connector with an ohm meter. You should have roughly 60ohms. The bus system has two 120ohm resistors wired in parallel, one on either end to eliminate unwanted voltages. Blowing one or both will drastically effect the bus operation. Best of luck,
-Derek
 

Trevor801

Member
Joined
Dec 5, 2016
Location
Nc
TDI
04 golf 12 sportwagen
thanks for the leads guys. Hoping to have a scan to post soon. Turns out they are not reading the 60 ohms between the two pins at the test port. If it is sounding like a fried resistor, where are they possibly located. Are they located in a module, cluster or possibly hidden somewhere in the harness. We can talk to and see the modules but are not getting a cel or glowplug light with key on. Trying to get the ecu powertrain back up and running.
 

Trevor801

Member
Joined
Dec 5, 2016
Location
Nc
TDI
04 golf 12 sportwagen
Finally got the scan. never done this before. hopefully it works. also tried plugging in a different abs module to see if that was bringing the system down. but still no change. no cel, no glowplug light.

VCDS Windows Based VAGNAS Emulator Running on Windows 10 x64 VCDS Version: Release 18.2.0(x64) Data version: 20180212 DS287.0
www.Ross-Tech.com
Dealer/Shop Name: Workshop Code: 000 00000 000000
Self-Diagnosis Log Wednesday, 18, April, 2018,08:18:13:54454
VIN: 9BWFR61J244036254 License Plate: Mileage: 609710km-378856mi Repair Order: 6666666
Chassis Type: 1J (1J - VW Golf/Bora IV (1998 > 2006)) Scan: 01 02 03 08 15 16 17 19 22 29 35 36 37 39 46 47 55 56 57 75
76
VIN: 9BWFR61J244036254 Mileage: 609710km-378856miles
VCDS
Self-Diagnosis Log Wednesday, 18, April, 2018,08:18:13:54454
Page 2
VIN: 9BWFR61J244036254 License Plate:
Address 01: Engine Labels: 038-906-016-BEW.lbl
Part No SW: 038 906 016 H HW: 028 101 114 6 Component: R4 1,9L EDC G000AG 6327 Revision: 12345678 Serial number: VWZ7Z0D9355209 Coding: 0150034 Shop #: WSC 08316 552 00000 VCID: 197A2B23D 14D048CFF-5184
6 Faults Found: 18058 - Powertrain Data Bus
P1650 - 000 - Missing Message from Instrument Cluster
Freeze Frame:
RPM: 0 /min Torque: 0.0 Nm Speed: 0.0 km/h Load: 0.0 % Voltage: 11.48 V Bin. Bits: 00001100 Torque: 0.0 Nm Torque: 110.0 Nm
18034 - Powertrain Data Bus
P1626 - 000 - Missing Message from TCU
Freeze Frame:
RPM: 0 /min Torque: 0.0 Nm Speed: 0.0 km/h Load: 0.0 % Voltage: 11.48 V Bin. Bits: 00001100 Bin. Bits: 00000000 Bin. Bits: 10000100
18057 - Powertrain Data Bus
P1649 - 000 - Missing Message from ABS Controller
Freeze Frame:
RPM: 0 /min Torque: 0.0 Nm Speed: 0.0 km/h Load: 0.0 % Voltage: 11.48 V Bin. Bits: 00001100 Torque: 0.0 Nm Bin. Bits: 00000000
18044 - Powertrain Data Bus
P1636 - 000 - Missing Message from Airbag Controller
Freeze Frame:
RPM: 0 /min
VCDS
Self-Diagnosis Log Wednesday, 18, April, 2018,08:18:13:54454
Page 3
VIN: 9BWFR61J244036254 License Plate:
Voltage: 11.48 V Bin. Bits: 00001100 Torque: 0.0 Nm Torque: 110.0 Nm
17978 - Engine Start Blocked by Immobilizer
P1570 - 000 - - MIL ON
Freeze Frame:
RPM: 63 /min Torque: 0.0 Nm Speed: 0.0 km/h Load: 0.0 % Voltage: 10.87 V. Bin. Bits: 00001100 Bin. Bits: 11000000 (no units): 0.0
17055 - Cylinder 1 Glow Plug Circuit (Q10)
P0671 - 000 - Electrical Fault - Intermittent
Freeze Frame:
RPM: 0 /min Torque: 0.0 Nm Speed: 0.0 km/h Load: 0.0 % Voltage: 11.17 V Bin. Bits: 00001100 Temperature: 18.0°C Bin. Bits: 00110000
Readiness: 14000
Address 03: ABS Brakes Labels: 1C0-907-37x-ABS.Ibl
Part No: 1C0 907 379 L Component: ABS FRONT MK60 0101 Coding: 0004097 Shop #: WSC 00001 785 00200 VCID: 3326F98B53E1DEDCD5-5184
No fault code found.
VCDS
Self-Diagnosis Log Wednesday, 18, April, 2018,08:18:13:54454
Page 4
VIN: 9BWFR61J244036254 License Plate:
Address 17: Instruments Labels: 1J0-920-xx5-17.lbl
Part No: 1JO 920 907 F Component: KOMBI+WEGFAHRSP VDO V03 Coding: 15234 Shop #: WSC 00001 VCID: 2C14E2F7DEDF812494-513C 9BWFR61J244036254 VWZ7Z0D9355194
8 Faults Found: 01177 - Engine Control Unit
65-10 - Unauthorized - Intermittent
01177 - Engine Control Unit
64-10 - Not Currently Testable - Intermittent
01312 - Powertrain Data Bus
37-10 - Faulty - Intermittent
01314 - Engine Control Module
49-10 - No Communications - Intermittent
01316 - ABS Control Module
49-00 - No Communications 01321 - Control Module for Airbags (J234)
49-00 - No Communications 01315 - Transmission Control Module
49-00 - No Communications
01304 - Radio
49-10 - No Communications - Intermittent
Address 19: CAN Gateway Labels: 6N0-909-901-19.lbl
Part No: 6NO 909 901 Component: Gateway K<->CAN 0001 Coding: 00006 Shop #: WSC 00001 VCID: 70AC36873277A5C4E8-513C
6 Faults Found: 01312 - Powertrain Data Bus
37-10 - Faulty - Intermittent
01314 - Engine Control Module
49-10 - No Communications - Intermittent
01316 - ABS Control Module
49-00 - No Communications 01321 - Control Module for Airbags (J234)
49-00 - No Communications 01315 - Transmission Control Module
49-00 - No Communications
01304 - Radio
49-10 - No Communications - Intermittent
---------------
VCDS
Self-Diagnosis Log Wednesday, 18, April, 2018,08:18:13:54454
Page 5
VIN: 9BWFR61J244036254 License Plate:
Address 46: Central Conv. Labels: 1C0-959-799.lbl
Part No: 1C0 959 799 C Component: 8C Komfortgerát HLO 0003 Coding: 00258 Shop #: WSC 00001 VCID: 373ECD9B179932FCE9-4B1E
Subsystem 1 - Part No: 1C1959801A Component: 8C Tõrsteuer.FS KLO 0202
Subsystem 2 - Part No: 1C1959802A Component: 8C Tõrsteuer.BF KLO 0202
Subsystem 3 - Part No: 1C0959811A Component: 8C Tõrsteuer. HL KLO 0202
Subsystem 4 - Part No: 1C0959812A Component: 8C Tõrsteuer.HR KLO 0202
5 Faults Found: 01330 - Central Control Module for Central Convenience (J393)
53-10 - Supply Voltage Too Low - Intermittent
01299 - Diagnostic Interface for Data Bus (J533)
49-10 - No Communications - Intermittent 00928 - Locking Module for Central Locking; Front Driver Side (F220)
54-10 - Incorrectly Equipped - Intermittent 00929 - Locking Module for Central Locking; Front Passenger Side (F221)
54-10 - Incorrectly Equipped - Intermittent 00930 - Locking Module for Central Locking; Rear Left (F222)
54-10 - Incorrectly Equipped - Intermittent
Address 56: Radio Labels: 3B7-035-1xx-56.lbl
Part No: 3B7 035 180 F Component: Radio 001 0016 Coding: 00401 Shop #: WSC 00001 VCID: 230609CBB3014E5C25-513C
4 Faults Found: 00881 - Connection to Speaker Rear Right
44-10 - Short Circuit - Intermittent 00849 - S-contact at Ignition/Starter Switch (D)
78-10 - Missing Messages - Intermittent
01064 - Terminal 58d; Interior Dimming
78-10 - Missing Messages - Intermittent
00625 - Vehicle Speed Signal
78-10 - Missing Messages - Intermittent
 

Seatman

Top Post Dawg
Joined
Apr 23, 2010
Location
Scotland
TDI
2014 Skoda rapid elegance 1.6 cr tdi
Could it be anything to do with the fact it was an auto? Is there anything left that could stop the car from firing up?
Like on the auto it has to be in neutral or park, is there still some controller hidden away to do with the auto box maybe?
 

pdq import repair

Veteran Member
Joined
Nov 6, 2016
Location
idaho
TDI
09 Jetta
From the wiring diagram this appears to be a simple CAN system with the CAN controller in the ECU. Since you put in a different cluster and ECU those should be ok. Are the cluster and ECU and key matched?


First step now is to unplug each component on the CAN and see if you get communication back after each one. I suspect something is pulling the CAN down and once unplugged the others should play well. I start at the ABS controller as it is fragile.
 

Rob_from_Elkmont

Veteran Member
Joined
Oct 13, 1999
Location
Heart of Dixie, USA
CAN is a robust physical interface. The CAN bus transceiver is designed to handle shorts to 12Vdc and to ground on a permanent basis. That said, I have seen transceivers damaged due to shorts. Specifically, transceivers from TI. pdq_import_repair's approach is a good one in my opinion.
 

Enabled

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Joined
Apr 23, 2013
Location
Houston, TX
TDI
2003 Jetta TDI Manual, BMW 328d SW
You can only really do the above test if you know which modules hold the 2 terminal resistors, or if they are separate in the harness.



Not sure if you already tried, but you need to check the resistance value between the two canbus lines (MUST be between 60-100 ohm for it to work), and the voltage of each vs. ground must be 2.5V or very close.

Don't throw modules at it yet.
 

Trevor801

Member
Joined
Dec 5, 2016
Location
Nc
TDI
04 golf 12 sportwagen
Got a chance to tinker with the car today. At the test port on getting no resistance. Just shows O. L. Tested resistance between the high and low at a couple other points like abs harness, tcm harness, an the factory crimps behind the dash and it bounces around between 0.0 and O. L. Sometimes throwing a few random number readings in between. I am getting close to the 2.5v on each at all locations except the test port. Trying to figure where the cluster wires come from. Could they be coming off the cluster? It is possible the second cluster I tried to swap in was no good. And possible the original is what is fried. I get all but glow plug and cel on the original and almost nothing on the other one except immo. The shop says it should show CEL and other lights without being key matched. I think I'm going to try a cluster from the junk yard tomorrow. I tried unplugging all modules I could get to. Abs, ccm, airbag, RSS, glow plugs Relay. Am I moving in the right direction? Are the possibly fried resistors in the cluster and that is why there is nothing happening on the test port?
 

Enabled

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Joined
Apr 23, 2013
Location
Houston, TX
TDI
2003 Jetta TDI Manual, BMW 328d SW
Sometimes the resistors can be external of a module on CANBUS networks. They may be at terminal ends.

Do you have wiring diagrams relevant to your car? Very difficult to do this kind of repair without wiring diagrams.
 

leafs

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Joined
May 28, 2018
Location
canada
TDI
alh
bro you gotta get the wiring diagrams and check for continuity and all that good stuff. obviously start at the circuit you sent the voltage down... and I'm pretty sure the cluster, key, and ecu all have to match for the immobolizer.
 
Last edited:

Trevor801

Member
Joined
Dec 5, 2016
Location
Nc
TDI
04 golf 12 sportwagen
Checked resistance again. Getting 2.3k everywhere except one port. Still O. L. There. Tried 2 more clusters with no change. I guess I need to start unplugging door locks and anything else that has can wires. Three different ecu, r different clusters, an abs module and still no comms
 

Trevor801

Member
Joined
Dec 5, 2016
Location
Nc
TDI
04 golf 12 sportwagen
I do have diagrams, still learning how to read them. Haven't seen where external ends might be located. I know the three modules must be matched for engine to run but the shop says we should still be able to get our check engine light and communication back up without it. Maybe that's not the case though.
 

Enabled

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Joined
Apr 23, 2013
Location
Houston, TX
TDI
2003 Jetta TDI Manual, BMW 328d SW
Yea, even if mismatched key and ecu, you would still have communication and half second of running.
Are those wiring diagrams digital or printed out? I've fixed a few BMW canbus systems, and the wiring diagrams are indispensable.
A simple test is to add your own resistance in a simple spot on canbus, and see how the system reacts. But you still need to trace the canbus wires beginning to end.

A module map would be awesome.
 

tgray

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Joined
Sep 12, 2004
Location
Marengo, IL
TDI
'02 Beetle, '05 Golf, 2000 Jetta, 2001 Jetta, 2002 Jetta
Unplugging doors is not that hard. The can bus runs through these. The more you can get out of the circuit the better having only the test port and the ecu and cluster hooked up. Start with the core parts connected and if no communication then you may have fried a wire itself. You should be able to unplug your comfort module and abs module as well and still gain communication with the ecu and cluster. (Dont forget the radio. That is in the system too.) Verify communication with only the ECU and cluster. Then start putting the stuff back together while checking. It usually is something simple and easy but you just have to find the issue.
 
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