Thread: D4 Electric Trailer Brake Wiring

The PDF version is suitable to protect vehicle from a Tow Pro failure that "may" send a high current out to the CJB. The diode is in the sense wire in this version.

However, this version does not illuminate the vehicle brake lights when the manual trailer brake button is pressed.

This issue is fixed by the version in the jpg file. The CJB is still protected but the brake signal can travel from controller to brake light during manual operation.

One issue with the jpg version: the diode size needs to be increased because 3A is potentially not enough for the full current required for say 4 x trailer lights. You may have noted a few people have increased diode size to 6A for this arrangement.

Regards,
Scott

Finally getting this down today... too much talking on the MOD Day... however a question for those that have run the cables.

Thanks again for this post.... so much useful information

On the rear wheel arch what did people do here? Behind my trim between the rear Seat belt bolt and the edge there are plastic perpendicular fins that impeded the cable to sit flat. See the photo.

There is no space behind the seat belt bolt

Did other simply cut them out, bend them over? (I am running the traxide and the towpro together

Didn't even pull that trim, just fed the wire under the edge that contacts the carpet..

Originally Posted by Tombie

Didn't even pull that trim, just fed the wire under the edge that contacts the carpet..

Thanks, did that... it was tight, but worked, Thanks Tombie.

(Just as well i liked practice on getting it under the B Pillar, ended up pulling it back through to do the rerouting )

Originally Posted by apom

Thanks, did that... it was tight, but worked, Thanks Tombie.



(Just as well i liked practice on getting it under the B Pillar, ended up pulling it back through to do the rerouting )

I just take the B pillar trims completely off

Originally Posted by Tombie

I just take the B pillar trims completely off

Yep, i was going to that... i just ran a trace front to back under it then taped it up and slowly pulled it through... easy as!!

The traxide and the towpro under the c pillar near the seat is the tightest point

Hi guys, I'll be fitting a traxide and tow pro elite controller this weekend hopefully if all the gear turns up. Fitting into a MY15 D4 HSE.
There is tons of info on here which has been very helpful yet I have one question unanswered.
Do I need to add in the diode if I have purchased the linear electronic design module?
Cheers

Originally Posted by Crofty

Do I need to add in the diode if I have purchased the linear electronic design module?
Cheers

Yes, they have two different functions.
Diode protects CJB from Tow Pro failure.
Module activates trailer assist by allowing vehicle to recognise trailer is attached.

Hopefully you noted the diode size detail (6A not 3A if upstream of splice).

Scott