[triffic]

I've just spent a few not-so-pleasant days fitting a Westfalia detachable towbar with full 13-pin electrics (my van does not have VW towbar prep) and mostly it went Ok.

The bar itself is really easy to bolt in place, but the electrics caused a problem - the result being that the brake lights on the trailer are on all the time.

The reason is that the instructions say to find a Black/Red wire under the drivers side dash and tap into that. However, when I look at the loom that they refer to (that leads to the 52-pin connector on the Network Control Unit below and to the left of the main lighting switch) there is no black/red wire - only a red/black wire, which is permanently live (hence brake lights always on).

So, does anyone (perhaps with a copy of ELSA) know where I can pick up a feed under the dash that is live only when the brake lights are on? The supplier wasn't very helpful - they acknowledged that other people had reported the issue, but just suggested that I "look around" for a suitable feed. On that control unit and the one next to it I have more than 100 wires to choose from, so any help narrowing it down would be appreciated!

 

[jenna]

Can't you tap into the brake lights at the rear? Sure someone on here could help with the colour wire in the loom on rear lights and can pick up a negative there too this is what I've done when fitting my reverse camera and needing a feed which only becomes live when reverse lights activated.

 

[triffic]

Can't you tap into the brake lights at the rear?

Thanks, but no. The CANbus controller is installed at the front, right next to the battery, and the wire that senses the brake light is in a loom that goes over the engine bay and into the rear of the dash at the drivers side.

It would I guess be possible to take a wire from the rear and run it all the way to the front, and connect it beside the CANbus controller in the engine bay, but as you can imagine I'm not eager to do that if the correct wire is in the loom that the sense wire is currently sitting next to!

The supplier says the correct wire is on the 52-cable connector that the red/black (wrong, permanently live) wire is on - they just can't tell me what colour it is...

 

[Deaky]

Had exactly the same issue myself. Looks like it's a RTFM problem H: looking closer it says to splice the RD/BK cable on the towbar loom to the BK/RD cable on the BCM black plug. I read that as join the red n black to the red n black. Wrong H:

This is the cable you need pin 43

Here you can see the wire that I wrongly connected to

Now if only I could sort the in coding out :blg:bhd

 

[triffic]

Thanks for that Deaky - I knew the difference between black/red and red/black (first is always the solid colour) but I couldn't find a black/red anywhere. Hence my red/black has teeth marks like yours, though I've hidden the evidence on mine! Now I know the pin number I can have a look and see what colour I have at connector 43.

The coding didn't seem to cause me any trouble - what version of VCDS are you using? IIRC there was one step not shown in the instructions - first you need to go to the CAN gateway and get the trailer CAN module (69) registered. Then enable "trailer active" in Central Electronics, then enable Trailer in Park Assist (if you have reversing sensors).

 

[Deaky]

I'm using the latest version. 12.12.0.

The module is showing as incorrectly coded in the CAN Gateway. I've gone into the gateway installation list and ticked 69 Trailer it's still showing as Control module incorrectly coded. I'm waiting for an email back of Ross

Here's my scan, if you can shed any light I'd appreciate it. T:

Chassis Type: 7H (6N0)
Scan: 01 02 03 08 09 10 15 17 19 25 56 69 0B

VIN: WV1ZZZ7HZDH108003   

01-Engine -- Status: OK 0000
02-Auto Trans -- Status: OK 0000
03-ABS Brakes -- Status: OK 0000
04-Steering Angle -- Status: OK 0000
08-Auto HVAC -- Status: OK 0000
09-Cent. Elect. -- Status: OK 0000
10-Park/Steer Assist -- Status: OK 0000
15-Airbags -- Status: OK 0000
17-Instruments -- Status: OK 0000
19-CAN Gateway -- Status: Malfunction 0010
25-Immobilizer -- Status: OK 0000
56-Radio -- Status: Not registered 0011
69-Trailer -- Status: OK 0000
 
-------------------------------------------------------------------------------
Address 01: Engine (J623-CFCA)       Labels: 03L-906-022-CFC.clb
   Part No SW: 03L 906 019 GL    HW: 03L 907 309 L
   Component: R4 2,0L EDC   H38 3567  
   Revision: 22H38---    Serial number: 00000000000000
   Coding: 01254012232400080000
   Shop #: WSC 02756 790 50316
   ASAM Dataset: EV_ECM20BTD01103L906019GL 003003
   ROD: EV_ECM20BTD01103L906019GL.rod
   VCID: 7BF51B7AF29BADC6C11-802E

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

-------------------------------------------------------------------------------
Address 02: Auto Trans (J743)       Labels: 0BH-927-711.clb
   Part No SW: 0BT 300 045 P    HW: 0BH 927 711 C
   Component: DSG DQ500-7F  H07 1803  
   Revision: 00H07V01    
   Coding: 0014
   Shop #: WSC 00000 000 00000
   ASAM Dataset: EV_TCMDQ500021 001001
   ROD: EV_TCMDQ500021.rod
   VCID: 428BA69ED5F11C0EC27-8017

No fault code found.

-------------------------------------------------------------------------------
Address 03: ABS Brakes (-----)       Labels: 7E0-907-37x-MK25AXT.clb
   Part No SW: 7E0 907 379 K    HW: 7E0 907 379 E
   Component: ESP MK25A XT  H43 0110  
   Revision: 00H43001    
   Coding: 108764AD09A4089D26A29071AA6110
   Shop #: WSC 02756 790 49152
   VCID: 3A7BDE7EB52154CE9A7-806F

No fault code found.

-------------------------------------------------------------------------------
Address 08: Auto HVAC (J301)       Labels: 7E5-907-047.clb
   Part No SW: 7E5 907 047 BM    HW: 7E5 907 047 BM
   Component: Climatic-T5   H20 0505  
   Revision: 00001010    
   Coding: 0000000002
   Shop #: WSC 02756 790 50316
   ASAM Dataset: EV_ClimaticT5 A01003
   ROD: EV_ClimaT5Basis.rod
   VCID: 7BF51B7AF29BADC6C11-802E

No fault code found.

-------------------------------------------------------------------------------
Address 09: Cent. Elect. (J519)       Labels: 7H0-937-08x-09.clb
   Part No SW: 7H0 937 087 K    HW: 7H0 937 087 
   Component: BCM T5GP H+4  H32 0407  
   Revision: BO032001    Serial number: 0533 068130002
   Coding: A0B0793A0A612413922848106C2B8CD50080410F60844000320000000000
   Shop #: WSC 02756 790 12345
   VCID: 3C77D866BF156AFE88B-8069

   Subsystem 1 - Part No SW: 7E0 959 801 B    HW: 7E0 959 801 B  Labels: 7E0-959-801.CLB
   Component: J386__TSG_FT  002 3313 
   Coding: 010000

   Subsystem 2 - Part No SW: 7E0 959 802 B    HW: 7E0 959 802 B  Labels: 7E0-959-802.CLB
   Component: J387__TSG_BT  002 3313 
   Coding: 000000

   Subsystem 3 - Part No: 7E1 951 172 
   Component: DWA-Sensor 00  001 0104 
   Coding: 000000

   Subsystem 4 - Part No: 1K0 951 605 C
   Component: LIN BACKUP HO  H05 1501 
   Coding: 000000

   Subsystem 5 - Part No: 7E1 951 172 
   Component: DWA-Sensor 00  001 0104 
   Coding: 000000

   Subsystem 6 - Part No SW: 3C8 959 537 D    HW: 3C8 959 537 D
   Component: E221__MFL-TK6  H07 0022 
   Coding: E30000

No fault code found.

-------------------------------------------------------------------------------
Address 10: Park/Steer Assist (J446)       Labels: 7E0-919-475.clb
   Part No SW: 7E0 919 475 L    HW: 7N0 919 475 
   Component: PARKHILFE 8K  H06 0106  
   Revision: --------    Serial number: 28261301100191
   Coding: 118101
   Shop #: WSC 02756 790 50316
   ASAM Dataset: EV_VW75XParkAssis8K 001003
   ROD: EV_VW75XParkAssis8K.rod
   VCID: 3B75DB7AB21B6DC6811-806E

No fault code found.

-------------------------------------------------------------------------------
Address 15: Airbags (J234)       Labels: 5K0-959-655.clb
   Part No SW: 7E0 959 655 B    HW: 7E0 959 655 B
   Component: VW10Airbag009 H07 0013  
   Revision: --------    Serial number: 003HL00GK3NH
   Coding: 000000000000000000000000000000003039
   Shop #: WSC 02754 790 50316
   ASAM Dataset: EV_AirbaVW10BPAVN750 A01026
   ROD: EV_AirbaVW10BPAVN750_VN35.rod
   VCID: 3561CD42943FBBB6775-8060

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments (J285)       Labels: 5K0-920-xxx-17.clb
   Part No SW: 7E0 920 970 G    HW: 7E0 920 970 G
   Component: KOMBI         H06 0605  
   Serial number: 00000000000000
   Coding: 460A01
   Shop #: WSC 02756 790 50316
   ASAM Dataset: EV_Kombi_UDS_VDD_RM09 A04716
   ROD: EV_Kombi_UDS_VDD_RM09_SE35.rod
   VCID: 2E53E22E7169886E36F-807B

No fault code found.

-------------------------------------------------------------------------------
Address 19: CAN Gateway (J533)       Labels: 6N0-909-901-6R.clb
   Part No SW: 6N0 909 901     HW: 7H0 937 087 
   Component: GW-K-CAN TP20 H32 0407  
   Revision: BO032001    
   Coding: 042300
   Shop #: WSC 02756 790 12345
   VCID: F0EFBC5623DD5E9EE43-80A5

1 Fault Found:
01044 - Control Module Incorrectly Coded 
            000 - -
             Freeze Frame:
                    Fault Status: 01100000
                    Fault Priority: 2
                    Fault Frequency: 1
                    Reset counter: 255
                    Mileage: 3215 km
                    Time Indication: 0
                    Date: 2006.14.07
                    Time: 00:30:56


-------------------------------------------------------------------------------
Address 25: Immobilizer (J334)       Labels: 5K0-920-xxx-25.clb
   Part No SW: 5K0 953 234     HW: 5K0 953 234 
   Component: IMMO          H06 0605  
   Serial number:               
   Coding: 000000
   Shop #: WSC 00000 000 00000
   ASAM Dataset: EV_Immo_UDS_VDD_RM09 A03709
   ROD: EV_Immo_UDS_VDD_RM09_VN35.rod
   VCID: EADBAE3E0D01A44EAA7-80BF

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio
Cannot be reached

-------------------------------------------------------------------------------
Address 69: Trailer (J345)       Labels: 1K0-907-383-MY8.lbl
   Part No SW: 1K0 907 383 F    HW: 1K0 907 383 F
   Component: ConWysTrailer H07 0100  
   Revision: 3A001001    Serial number: 00000132425721
   Coding: 0100000100000000
   Shop #: WSC 00007 223 174336
   VCID: 306FFC56635D9E9E243-8065

No fault code found.

-------------------------------------------------------------------------------
Address 0B: Sec. Air Heating
Cannot be reached

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

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Address 19:6N0 909 901  recoded (Installation List) from 5F0B1C0000 to 5F0B1C0000

 

[triffic]

It's only 2 weeks ago that I did it and the details are getting hazy already.

But I'm fairly sure the first step is to access the CAN gateway itself (address 19) and from there you can change the coding to register the trailer module (address 69) - without this step the gateway knows it's there but seems not to want to talk to it properly.

Once that's done the CAN gateway error message goes away and it's just a quesion of selecting the other two options.

 

[Deaky]

Done that. Gone into the CAN module 19, ticked Trailer module 69 then set tow hitch installed in the park assist module. Still getting this module incorrectly coded error and the van doesn't recognise that the trailer is hooked up. All the lights work though :*

 

[triffic]

Thanks for the photo Deaky - looked again today and discovered it was me not looking hard enough! My excuse is that it's a ~really thin~ wire and it looked all black in the poor lighting when I first looked... So, all working well now, and it automatically cuts out the rear fog light and uses the trailer's one instead when it's plugged in. I haven't yet tested to see if it cuts out the rear sensors yet though.

Did Rosstech get back to you? One thing I forgot to mention is that I got prompted for a password before it would allow me to add module 69 to the CAN gateway Installation List. Did you get that?

 

[Deaky]

Well apparently it's worked all alongLOL:

Ross Tech are still yet to reply but I've spent the last 4 days tralwing the internet. The control module incorrectly coded message I'm getting on VCDS is nowt to do with the tow bar. It's been there since I had the van :*

All along I've been looking for a tell tale flashing light on the dash when the bike rack is connected - like my car does. Turns out there isn't one I:. So the looms been working as it should. I took a bulb out on the rack and the dash indicator light flashed twice as fast and the bulb fail light came on. H:

The only slight problem I have now is when the fog lights are on and the bike rack is plugged in then neither the van or the rack fog lights come on. If I untwist the 13pin plug but leave it plugged in so the van thinks it's disconnected then the fog light on the van and the bike rack come on. Maybe it's something else I've missed I:

Just celebrating with a beer now :cheers

 

[triffic]

Ok - that sounds not too bad. I had odd behaviour with the fog light as well (showing bulb failure when bulb was Ok) but that seemed to sort itself out. I think it may have been because I had the ignition on when I plugged it in once.

I was wondering whether the error message was simply that your RCD310 (or whatever) original radio is disconnected or no longer present. Assuming that's not temporary, have you tried removing it from the installation list? As supplied, my RCD310 showed as "incorrectly coded" just because the coding was for 2 speakers and it had actually had a second pair added as part of the conversion.

 

[Deaky]

Swapped the wires over under the seat and everything's workings as it should A:

I had the same thought about the radio but when I checked it isn't in the installation list anyway :*. It must be that that's throwing up the error on the CAN module but everything seems to work fine so I'm gonna leave it alone T:

 

[Nokampa]

I'd just like to say thanks for posting this! I've been having trouble with the brake lights staying on since fitting the towbar.
Some additional points to note that I've learned. The black connector block is best removed from the holder then the actual harness unclips from the connector block and then it's actually two connector blocks slid together.... slide them apart and you'll find the wire/port numbering.

Hope that saves someone a bit of time and swearing!