The plug is on a pigtail lead in the battery box, under a panel , which is under the drivers feet. I had hoped that this lead would make the brake controller easy to install, but the Sparky told me that, for whatever reason, the blue brake wire had been omitted. It is a four pin plug, but only has 3 wires!. This meant that he had to run the new blue wire to the back of the car anyway. I don't know who thinks up the Australian specs. I did read that an owner of the latest Q7 used the plug directly with no issues. That must be why the Audi costs more - you get the full wiring system!
Good Luck
Steve

 

Hi Steve,
Many thanks for the info. It looks like I may need to do the same then. I'm also planning on installing a remote controlled transceiver, which will probably have to be mounted behind the trim in the cargo compartment, so it will be another wire in the bundle I'll need to install. I'll post here once it's done!

Thanks again for your info.

Mal.

 

I found the pigtail in the battery box. It is long enough to go up into the drivers dash panel, so it might already be in that position. It is a lead with the plug covered in foam for protection.

 

I found the connector in the battery box as Steve said. Only three wires there as well!! At least as you said there's enough length to make it forward under the instrument panel to install the brake controller there.

 

You're correct Brickwalls. Pin 1 is ground (brown), pin 2 power (red/white), pin 3 brake signal (black/red), and pin 4 will be the wire (nominally blue) you run back to the blue wire for the trailer brake power.

 

I have put this together for those who has their installer looking vacant 👓📋

 

Thanks for the information, I'm about to start installing the Redarc controller. Is the blue trailer brake wire already fitted to the Touareg CR or does it have to be added

 

Thanks all.

I'm going with a Tekonsha Prodigy P3 Controller again. Not that I tow much - quite the opposite. I find P3's inertia smarts on bumpy tracks minimises choppy braking. If a BC can tame Caravan braking on rough tracks,
- roads are no issue.

 

OK I have seen a 7L version of the:

[General body repairs, interior; Rep. gr. 70 ;]

and used it to remove & refit the:- [Luggage compartment trims]. And I found It was close enough to use for the 7P too.

However the CR, has sufficient differences to see if there is a CR version of the [General body repairs, interior; Rep. gr. 70 ; Luggage compartment trims] floating in the WWW ether.

 

I will PM them to you mate

 

Sorry about two pictures, but the single blue wire can be seen going into a white connector then white wire just to the left of centre.

 

Isn't the G508 plug under the steering column used to connect the brake controller. By your diagram it has the blue wire out of pin 4. What's the connector in the battery box?

 

The G508 plug was originally in the battery box in the CR model, but the cable was long enough to relocate it to run up behind the lower A pillar trim and bonnet release to the area under the steering column.
I'm also in Brisbane if I can be of any help.

 

Thanks, that clears up the location of the plug. I only joined CT today so am soaking up the info available here. Can you give me any info on how to access the battery compartment as well as trim and interior panel removal required for running the blue wire
thanks

 

The battery is under a removable panel on the driver's floor. Use your fingers to lift up the inboard edge of the panel by pulling up until the 2 clips disengage, then remove the panel.

I'll find the instructions for removal of the trim panels at the rear, and try to post here soon.

 

Must be a low profile battery

 

It's in a deep box!

 

Has anyone located the THRL (2 wire) Connector for the Brake Controller Output (Blue). I believe it should be somewhere between the 508 Connector and the 13pin Trailer Connector wiring harness.

VW did not provided the EBC Blue Output wire in the OZ harness, so I have run my own through to the 7 pin Trailer Connector.

However, I think a better solution would be to patch it in at the THRL Connector. I imagine it will be behind the Left Side Rear Trim Panel close to the Trailer Detector Module. That is unless OZ VW have repurposed that wire and Trailer Connector Pin5 for Earth Detection. I'd appreciate confirmation as I don't wish to just go rippling out trim on an exploration and risk breaking trim clips.

 

Hi brickwalls, check my picture in post 15. The blue wire is there in the harness. In my case, I replaced the 2 pin connector (black) with the white one almost centre in the picture. That blue wire goes to the trailer socket. The white wire it connects to in my picture runs forward to the brake controller up front.

 

Thanks for the confirmation Malaudi.
I saw that photo and noted it wasn't a VW connector so wasn't sure of the setup.

I didn't want to tear up the trim again if the Blue wire in the 7pin connector only went as far as the 13pin EU connector. If I can pick up a feed up at Trailer module it will be more factory than tapping it in at either of the 13 or 7 pin connectors which I had to do in my 7P.
Cheers.

 

Thanks yes I noticed something similar to them under them door sills when I ran the blue wire 6mts ago.

Unfortunately the blue wire from the 508 to the rear was missing in my model (& in my last one too) maybe the Launch model was a universal production harness.

Thanks for the coding tip. I did a before & after towbar installation backup but hadn't got around to doing a side by side comparison to revert the code. I'm hoping they didn't delete the sensors from the bumpers. I crawled under an saw they'd unnecessarily cutout 120mm either side of the hitch, which only required the left side done. I can't see the Lateral Antennas via the hole. Another Dealer did my last V8 towbar installation and they deleted the Antennas (claimed it was part of VW instructions). Since it has to go back for "complementary" body & bumper scratches repairs. I'll attempt to get them to revert the kick open. I'm particularly pissed off this time as I gave clear instructions on what I wanted and requested a mechanic that had prior experience.

 

Unfortunately the blue wire from the 508 to the rear was missing in my model (& in my last one too) maybe the Launch model was a universal production harness.

@ brickwalls & Malaudi
As a matter of interest does your vehicle build include the PR code "1D8"
That decodes as <Trailer hitch preparation> and may be the tell tale on whether the wiring is included or not?
I have it.

 

Sorry for the late reply brickwalls. Yes I have the same white and green wires under the rear sill, and also similar wires under the door sills too as mentioned by evaddirb. I don't know what they're for, but I'm sure they're not the antenna for the kick function of the rear door. That antenna is attached to the underside of the rear bumper just to the right of the towbar. That function works still on mine, so I imagine it's a coding issue as evaddirb mentioned.

I also didn't have the fourth wire in the brake controller connector (G508?) that runs from the rear to the front, hence my running that white wire forward as seen in the picture. I changed the VW black connector on the blue wire for a more heavy duty one as firstly I didn't have one that would mate with it, and secondly I wasn't convinced it could handle the current necessary to operate the brakes.

 

Yes when I saw the connection size and pulled apart the black housing and looked at the crimping job, I thought is was too light on as well. The wire gauge was OK, but the tongue and crimping were low grade IMHO. Brakes are normally only applied for short and pretty intermittent intervals, but going down the Escarpment into the Gong would test that OEM connection.

I decided to tee off the Harness wire with a short strap to a higher duty connector, which will still facilitate faulty finding or isolation if necessary. I just left the original connector intact in case it was part of some VW's diagnostic process.

 

I just checked and PR code "1D8" is not on my list, even though my CR is a launch edition 190 with Innovision pack too. I guess there must still be some variations in what's included.

 

Hi Guys,
I am picking up my 2019 190tdi launch edition next week. Have just bought a Redarc tow pro elite.
I will install it myself.
After reading everything everywhere about where the g508 connector is located, i'm still confused.
Is it, under the passenger dash?, if its in the battery box, is it under the drivers or passengers seat or in the drivers foot well. Is it easy to remove the seat?. Other forums have said, if its a LH drive, the battery box is under the drivers seat. If its RH drive, under the passenger seat. Has anybody got a good photo of that G508 connector. Is there plenty of slack with the G508 wiring loom, to have good easy access to it?
Many thanks for any help offered.

 

Hi Guys,
After reading everything everywhere about where the g508 connector is located, i'm still confused.

Some have reported to find it in the battery box under the drivers feet with length to get up under the dash.
I found it under the steering column on my 2019 Launch.(with a foam shroud around it)
Others didn't find at all.

 

The connector in my 2019 Launch edition was in the battery box, with sufficient length to re route it up behind the lower A pillar trim to under the instrument panel. As you'll see in previous posts, I've run an additional 4th wire not included in that connectors wiring bundle to the blue trailer brake wire located near the trailer module at the back left of the car. The battery is located under the drivers feet.

 

Hi Guys
thanks for your replies.
Where and what is THRL ?
Thanks again

 

Where and what is THRL ?

It is a electrical plug connector shrouded in foam in and around the passenger tail light, trailer module area.
When checking with a multi-meter you will see it connects to pin 4 of the G508 plug under the steering column

 

Hi Guys, thanks for your replies. Picked up my launch edition treg, wired my redarc brake controller up, no probs, connector was in the battery box. Just cant find where to put the remote head in the dash. Pulled everything out that I could in the dash. couldn't find a spot with enough depth. Would somebody post a photo of where they put their remote head, and possibly what was pulled to get to it. Thanks in advance

 

Mine was put on the right side of the steering column.

 

Just a quick question, have any or all of you, fitted the redarc EPDK device ie: diode, on your launch Tregs?
Thanks

 

So far I've completed the wiring for the brake controller, just need to plug it in. I'm thinking about the diode though. The brake controller is triggered by pin 3 of G508 (black/red wire) from the trailer module, but in addition to being triggered by that wire, the redarc controller also sends a 12V signal up that wire to activate the brake lights when the redarc intervenes. I'm just wondering how the trailer module will react when 12V is applied to it from the redarc (red trigger wire) back into it? If I was to install a diode, it would probably be there. I'm waiting to borrow a friends trailer to plug into the back so as to activate the trailer module and then experiment with that trigger wire.

 

Hi Malaudi
just got the van. The redarc isnt calibrating, and stays green, spoke to redarc tech. need 12v coming in to red trigger wire when brake lights come on. this isnt happening. need to do some fault finding tomorrow morning. brakes on van work, van brake lights come on, but no proportional. As to the diode,or not, he said definetely put it in, but only causes a problem when you manually push the button in without it. More when I find the problem

 

Need to find the trailer control module , where is it?. and how do you access it??
Thanks
Michael

 

Hi Michael,
The trailer control module is located behind the trim at the very back left side of the car. See attached picture - it's top and centre of the picture. You'll need to remove some trim there I think starting with the rear boot sill which just pulls straight up.
I'll be interested to see what you find re voltage from the signal wire to pin 3 of G508 as I assumed it will provide 12V when the trailer module detects there's a trailer connected and the brakes in the car applied. On the wiring diagramme I have that wire runs direct from pin 6 of T10 a black 10 pin connector on the trailer module to pin 3 of G508 that you've already located.

I'm hoping to borrow a trailer on the weekend so as to activate that module and see if my theory is correct. Failing that I'll make a trailer plug with resistors to simulate lights so the module thinks there's a trailer connected.

Anything further you think I can help with let me know.

Mal.