Towbar electrics for Xsara Phase II Saloon

[einsteinagogo]

I'm going to have to sit down with a notepad and pen, and take photos, write down all the wires, where they go from lights to relays and tor bar socket, to try and work out what is going on here.

[wheeler]

OK so just had a thought was just looking at some rear lighting wiring diagrams & noticed that the pin assignment of the rear lights is different, for example the rear brake lights on the right hand side lamp unit pin 1 is the power to the brake lamp however on the left hand side it pin 7 that is the power to the brake lamp.
With this in mind is there any possibility that you have mixed up the left & right lamp connectors?

[einsteinagogo]

It’s not possible to mix right and left as the loom is a specific length to reach left and right light clusters and the right side is where the relays are installed on the bulk head in the boot as per instructions , and instructions correctly identified the grey wire which connects to loom on the right

Do you have diagrams for light clusters at rear of a Xsara 2.0 HDi 90bhp MkII 52 plate for me to start working on a wiring diagram to see if I can spot anything obvious if there is a cross wire in the harness

[wheeler]

Was just a though incase the loom was symmetrical, There is not a diagram for the light clusters, its individual diagams for each circuit so easier just to type out.

LEFT LAMP
1- not used
2- Reverse
3- fog lamp
4- Earth
5- Indicator
6- Tail
7- Brake

RIGHT LAMP
1- Brake
2- Tail
3- Indicator
4- Earth
5- Fog Lamp
6- Reverse
7- Not used

[einsteinagogo]

Is right and left from front or rear of car ?

I imagined that both connectors would have been the same! Clearly not! Eg the PIN numbers but I can see a sort of pattern

[PaulC5]

Left and right are normally taken when looking forward from the driver's seat. If stood behind the car it is as if you are still looking to the front of the car.

[einsteinagogo]

Thanks interesting need to check tomorrow because I’m sure earlier Left Hand Side - Left Lamp - Pin 7 was not used ! Pin 7 on the plug

Or it’s get the meter out

[wheeler]

Left and right are normally taken when looking forward from the driver's seat. If stood behind the car it is as if you are still looking to the front of the car.

I would agree with that

[einsteinagogo]

Just coming back to this things I’ve noticed the wiring loom had a connection going to the relay for left fog - which didn’t seem correct, and there was no link to left fog - which also seemed odd!

I found another wiring loom same part but it was wired completely differently interestingly as far as tested at present seems to function correctly - only issue is the sour to tow bar is far too short!

So tomorrow I’ll make up a hybrid between the two!

Like always probably would have been cheaper to go to a tow bar fitter - but that would have given me the satisfaction of doing it myself! Report back soon

[wheeler]

Just coming back to this things I’ve noticed the wiring loom had a connection going to the relay for left fog - which didn’t seem correct, and there was no link to left fog - which also seemed odd!

May be because only a right fog lamp is required, a left fog lamp is optional.

[einsteinagogo]

Should not flash it though

And I thought if fitted needed to function on a MOT?

[Paul-R]

The two fog lamps (if you have two fitted) have to be functional for the MOT. They do not work independently though so a feed for the towbar electrics only needs to pick up a feed from one of them. Whether or not that will feed a single or double foglamp then depends on the make-up of whatever's plugged in to the socket.

[einsteinagogo]

Yes, I thought I'd red if fitted they need to function.

One loom is part right, and the other is part right, between the two should be able to make one work!