v40 towing electrics wiring .. help ..

[leejay2005]

hi there guys im new to all this forum stuff .. would jus like to say i have a v40 estate .. i have jus fitted a tow bar with half electrics . when i say half .. i mean i have indicators and break lights working on my caravan but i cant seem to get the sidelights to work .. i was just wondering if any member or admin have the details to which wires and where i am going wrong ... please ...
many thanks ..
lee ....

[CSE1Steven]

My first post on a forum.
I have a 2004 V40 Classic which I had fitted with a Towsure towbar. This was
the first problem, the towbar did not align correctly and had to have an
(approved) packer fitted.
When it came to the electrics, I decided to do the installation myself, as I
have an electrical engineering background. I decided to fit the 13 pin socket,
and use the popular TEB7AS and TEC3M relays. The first problem I
encountered was that I could not find a wiring diagram for the V40 Classic.
Plenty of diagrams were available for earlier models, but when checked
against the wiring colours on my car, not a lot matched. I suspect Volvo must
have used up any wiring looms left of the shelf for this final model ! In some
places, wiring colours changed either side of a multipin connector.
The relays were mounted near the rear N/S lamp cluster, as this is where
most of the cables which needed tapping into were located.
The colours on the TEB7AS were wired into the following car harness colours.
Yellow. Blue/Yellow. N/S indicator.
Green. Yellow/Brown. O/S indicator.
Blue. Blue. Fog.
Brown. Green/Orange. O/S tail. (see comment below)
Red. Green/Red. Brake lights.
Black. Blue/Red. N/S tail. (see comment below)
Grey. Purple/White. Reversing lamps.
White. Earth. Connected to stud near N/S tail lamp.

Comments. O/S and N/S tail lamps are usually a seperate supply, so if a
fault occurs, you only loose lamps on one side of the vehicle.
Because the V40 has multiple lamps across the rear of the
vehicle,some of which are in the boot lid, it appears that
those in the lid are one circuit, and those on the corner of
the rear are a seperate circuit. Hence with the Brown and the
Black on the relay one is taken from the boot lid feed and the
other from the main fixed lamp feed.
I ran a seperate fuse feed from the battery the feed the TEC3M, but I
probably wasted my time. There is a connector already in the harness in
the N/S corner which seems to become live on the engine starts, and it
is supplied with 2.5 or 3mm cable.

If I had not had any electrical skills, then this would have been a daunting task.
I hope this might save someone the stress I had tracing wires that are
not all the same colour from start to finish.