Headlight switch cable identification

[The Flying Scotsman]

I’m still trying to sort the issue I’ve got with my THQ lights.
I’m pretty sure I know what’s causing the problem.
There has been 2 wires tapped into the wiring going to the light control switch. A red and a blue wire.
I’m not sure what they are for and I’ve spoken to the company that converted my van and they have said they had not fitted them.
So still no idea what they are for.
If I knew what the wires they are connected to are for then hopefully they would give me and idea.
I know the black wire is and ignition feed. But not sure what the red and black wire is. Any ideas?
I’m going away in it next week so I’m at the stage of just cutting the blue and red wires and waiting to see what if anything stops working.
If they are required I hope to move them off of the lighting circuit. Which is super sensitive apparently.
Cheers

 

[DJHJKH]

Check the wiring diagram in members download section. Looks like someone has tapped into 2 live feeds one from fuse 32 and the other from fuse 8.

T6 - H7 Headlight Wiring Diagram

H7 Headlight Circuit Diagrams Please check the history/updates tab, first release is for early T6s manufactured from June 2015, second release is for vehicles manufactured from June 2016 onwards VIP Membership is required to download this document

www.t6forum.com

 

[Deaky]

Black wire is Terminal 15 ignition live. Red/black wire is Terminal 30 constant live. Brown is earth, Grey/blue is instrument lighting. All others go to the BCM to control your lights.

 

[oldiebut goodie]

Looks like they have used extremely heavy wiring not suited to where they have tapped into. I hope that the current draw is not commensurate with that extra wiring.

 

[The Flying Scotsman]

Thanks guys. So it’s an ignition live and permanent live they have used for something.
I’m going to pop off the lower dash again and see how far back I can trace them. Might give me an indication of what they are for.
Then I think I’m going to cut them to see what if anything stops working and if something does stop working then I’m going to take them to the internal fuse box and pick up an ignition and permanent live from there. So that they are not attached to my light circuit.
Hopefully this will stop the fault I’m getting with both my front and rear THQ lights.
I will update this thread with my progress as THQ have never come across this problem before.
Cheers

 

[Pauly]

My guess is bumper DRLs or dashcam ?

 

[The Flying Scotsman]

My guess is bumper DRLs or dashcam ?

I’ve disconnected the DRLs and the fog lights, removed the pin wire I added to the light switch plug and refitted the original light switch.
Also no dash cam.

 

[The Flying Scotsman]

My guess is bumper DRLs or dashcam ?

Everything works fine.
Then after about 5 minutes of the van running I hear a click like a relay then the bulb out light comes on on the dash and the main rear THQ lights go off but brake lights reverse and indicator lights work.
Also the DRLs in the THQ headlights turn off but the main beam stays on.
Then the next day no light on dash and everything working
For 5 minutes

 

[The Flying Scotsman]

I’ve done some digging and taken off dash panels and chased those wires. They go to a box. Definitely aftermarket.
Possibly an old tracker ?
I’ve taken pics of both sides of it.
Any idea guys?
I’m hoping to just cut the wires off that are attached to my light switch wires.
Do you think this will cause any problems with my van ?
Cheers

 

[The Flying Scotsman]

I’ve unplugged the mystery box and it’s still flashing away.

 

[oldiebut goodie]

https://www.manualslib.com/products/Novatel-Mt-1200-9082795.htm

 

[The Flying Scotsman]

https://www.manualslib.com/products/Novatel-Mt-1200-9082795.htm

Just comes up 404 page not found.

 

[oldiebut goodie]

Try this one:
NOVATEL MT 1200 USER MANUAL Pdf Download

 

[The Flying Scotsman]

I’ve stripped out that box and its loom. Everything in van still appears to be working.
I’m still getting the problem though.
It sometimes clears after I’ve turned the van off and back on. But a short drive later light goes on on my dash and the main rear lights go off.
I’m at a loss as what to do next. I was sure it was those wires attached to my light switch.
Back to the drawing board now unfortunately

 

[The Flying Scotsman]

Try this one:
NOVATEL MT 1200 USER MANUAL Pdf Download

Thanks.
As I thought a tracker.
It’s binned now.
And apparently not what was causing the issue.

 

[BGW1995!]

Hi guys just jumping on this thread as its relevant to whats up with my T6. What port is the dipped headlights on passenger side (front left). Can't figure out the diagram to know whether its the yellow and black. Could someone please confirm I've had a multi meter on and still wont test.