Berlingo B9 Tow Bar Electrics Guide

[Hardnut]

Guide on my Berlingo 2011 B9

** This is guide only, I am not responsible for any damage to your car**

With Both Rear light clusters removed for ease of access to wires.
I used a relay device from Towsure for Elec parts LINK  *Parts can be found else where. 
This came with scotch locks, but I used solder approach

Disconnect the Battery from the Positive side so no work effects the car.
Connector just lifts, but may find it greasy, gloves recommended.
   

Rear passenger side panel needs to be removed from the Boot area.
A post from Patch LINK with youtube  shows very well how to remove the panel
https://www.youtube.com/watch?v=TyXPgijQ...e=youtu.be

I found loosening it from the inside of the car closest to the seats best which also kept the popper at the rear of the boot intact. Just need to pull panel then twist up panel and push out when removing.
           

[Hardnut]

Remove the Grommet you can see in the picture to feed the towbar electrics into the car then place a hole in the grommet for the cable to travel though, then replace the grommet back.
   
Cable was zipped tied under the car at the highest points so not to catch wheels or and road. Mind pinch or rub points, as not to Damage the cable.

Rear drivers side, has two screws, one large plastics as seen in cubby and one behind the Torch if you have one, which screws to a black panel.
Torch just unplugs via the white plug to green PCB board. 
           

I fed some two pair audio wire up and over the boot area via the rubber trim for the tail gate, pushed into the plastic trim at the lower sections.
   

At the drivers cluster I pulled the audio wire to exit the car via a vent to the cluster wiring and did my wire stripping and soldering here, then when pushed back with cluster it ends in the car body dry and safe. Recovered with the fabric and electric tape to keep in place.

[Hardnut]

Thick White wire is found on the passenger side of the car which is dead till a Maxi fuse is added, but we leave that till last.
My technique for adding the wires is to score the outer cable then pull apart gently.
With Copper exposed push small screw driver between copper to make a hole.
The cable being added to the Car loom, needs to have its end stripped exposing copper.
I found twisting then pushing though loom hole then un-twisting and wrapping around each side gets good cover of existing cable.  
   

Then solder the two cables together, then warp in electrical tape. *I thought of heat shrink but then didn’t want to spilt the car loom to get a tube of shrink on*

Repeat above for all the colour cables needed, careful not to cut the cable completely.
*I cut two cables, but able to solder all the back together*
 
Electric pack came with instructions for relay box and to the car loom
   

I also research before and found notes from another thread at Single track LINK
"Copying notes"
 
Wiring is as follows;
Designation: Vehicle wire colour: Trailerboard wire colour
1(L), LH idicator: pink: yellow
2(54G), Fog lights: green: blue (this wire is not connected within the trailerboard).
3®, Earth, green and yellow/ bodywork: white.
4®, RH indicator: Purple: Green.
5(58), RH tail/ side/ numberplate: beige: brown.
6(54), Brake lights: white: red.
7(58L), LH tail/ side/ numberplate: grey: black.

Picture of work with colours taped and paired up. Extra Red cables to Brown and Green is the audio cable used for the drivers side cluster.
   

The White earth cable from the relay box can go on a handy Earth point where two existing cables are already place. My kit came with little loop which could add to the cable and add to the earth point. Just unscrew nut and replace.
   

[Hardnut]

In the Engine bay a new extra 40amp Maxi fuse is needed to make the thick white wire permanently live.
Right of the Battery is the fuse panel, 3 clips need moving so that you can pull the whole section up
   

NO cables need disconnecting I found when placing in the Maxi fuse.
Maxi fuse needs pushing into second slot from the left as seen, this filled the gap in between to other fuses.
   

Tested all lights for the car before putting all parts together. Relay box got zip tied to some form found in the passenger panel and pushed back in large gap found.

Trailer lights worked first time when it came.

[Trevor]

Very comprehensive thank you

[Hughzie]

Very interesting read. On my previous 14 plate I had a mobile Tow Bar fitter come out and fit a bar but he had issues with the wiring and I think you've just solved the reason why.
He couldn't get a permanent power supply and after 2 hours of trying it ended up getting left where the trailer electrics only worked if the light were on!
Given I only towed a 3x4 trailer half a dozen times a year I just made do with it. Never bothered getting a new tow bar on the current one but it seems clear after reading this the thick White wire was what the issue was as no extra fuses were added during the install.

[ash2020]

In the Engine bay a new extra 40amp Maxi fuse is needed to make the thick white wire permanently live.
Right of the Battery is the fuse panel, 3 clips need moving so that you can pull the whole section up


NO cables need disconnecting I found when placing in the Maxi fuse.
Maxi fuse needs pushing into second slot from the left as seen, this filled the gap in between to other fuses.


Tested all lights for the car before putting all parts together. Relay box got zip tied to some form found in the passenger panel and pushed back in large gap found.

Trailer lights worked first time when it came.

Hey, thanks for a fantastic step-through. It all worked apart from the white wire. I took out the ECU, put a 40A maxi fuse in the second slot, but still nothing on the thick white wire. Any ideas? Thanks.

[Hardnut]

Not a mechanic or auto electrical.

Simple checks did the fuse go in the correct place ? 
Lifted up the main fuse panel and found the maxi fuses under it ? 
Started at the left and found the 40 maxi GAP then 50 maxi ? New 40max goes between them ? So 40 40 50 from the left side. 
Is it pushed in all the way or right way round. I don't think makes a different the way round but i would follow the others.
Is the power connection at the tow relay good ? not broken or forgotten to do or placed in the wrong place ?
Got the earth wire connected ? 

What year is the car ? 

Could add photos ?

[Luthieronz]

In the Engine bay a new extra 40amp Maxi fuse is needed to make the thick white wire permanently live.
Right of the Battery is the fuse panel, 3 clips need moving so that you can pull the whole section up


NO cables need disconnecting I found when placing in the Maxi fuse.
Maxi fuse needs pushing into second slot from the left as seen, this filled the gap in between to other fuses.


Tested all lights for the car before putting all parts together. Relay box got zip tied to some form found in the passenger panel and pushed back in large gap found.

Trailer lights worked first time when it came.

Hey, thanks for a fantastic step-through. It all worked apart from the white wire. I took out the ECU, put a 40A maxi fuse in the second slot, but still nothing on the thick white wire. Any ideas? Thanks.

I was wondering did you get anywhere with the thick white wire issue. I am having the same issue. I added the 40A maxi fuse to the empty slot behind the ecu but this did  not power the thick white wire. Thanks.