XC90 - Westfalia Detachable towbar fitting guide

[indiebands]

Originally Posted by Coconut

Hi Tom,

The cable harness number you mention is different from the one I bought - Mine was part number 30756530 ( £15.26 + VAT ).

The trailer module ( Control Unit ) number is the same. ( £27.91 + VAT ).

These were the only two electrical parts I needed - the Cable harness has the 7 Pin socket on one end,
and 3 x factory moulded plugs on the other end, plus an Earth eyelet.
( AFAIK The smallest of the 3 plugs is not used on the 7 pin 12N wiring set up ).

The grey and green plug connects into the Trailer Module,
and the black plug connects into the fuse board behind the rear nearside trim panel as described earlier.

The wiring instructions for the 7 - pin set ( 12N ) describe selection of ONE of the following options via Pin 2 of the 12N socket :

Rear Fog Lamps, or
Charging, or
Reversing Lamps

I went for rear Fog Lamps being the one I thought I would need most often,
( and which I probably need legallly in the UK ? ).

Selection is made by inserting ( push to click lock ) one of 3 wires from the harness into the appropriate position on the appropriate plug.

I have no idea what would happen if you just connected up the black socket to the fuse box, with the other plug left free ( no Trailer board ).

I have no information on 13 pin wiring or additional 12S socket wiring.

Hi Coconut,
Thanks for the quick response. I did forget to mention that the Thule G5 909 needs a 13 pin connector, so that would explain the different part number for the cable harness. The trailer module price works out to 68 GBP, so I guess parts are more expensive here. I guess I can check eBay or US suppliers.
Cheers,
Tom

[Ron_XC90]

Hi Tom,

I'm using the Thule 909 with a 7 pin socket and a converter from 7 to 13 pin's. Works fine.... If you're not going to pull a caravan I wouldn't bother with a 13 pin socket t.b.h.

[XCF]

Indiebands.

You need to buy the trailer module whether you opt for 7 pin or 13 pin wiring.
The price last year from Volvo in the UK was around £50 all in for 7 pin and £100 for 13 pin (slightly discounted prices from Simon at FRF Volvo. See his details on the forum elsewhere).

Here's the details I have left from Simon which matches what you were quoted for 13 pin ...These were early 2010 prices.

7 Pin Wiring Kit: [30756530]
Retail Price £19.93 / Our Price £16.34
Trailer Module: [30664974]
Retail Price £36.44 / Our Price £29.88

Or:
13 Pin Wiring Kit: [30756531]
Retail Price £84.20 / Our Price £69.05
Trailer Module: [30664974]
Retail Price £36.44 / Our Price £29.88

Don't forget that even though the Thule 909 requires a 13 pin you could get away with the 7 pin wiring loom if you buy a 13 pin to 7 pin adaptor - though to be honest probably better to get the 13 pin these days.

[indiebands]

Originally Posted by XCF

Indiebands.

You need to buy the trailer module whether you opt for 7 pin or 13 pin wiring.
The price last year from Volvo in the UK was around £50 all in for 7 pin and £100 for 13 pin (slightly discounted prices from Simon at FRF Volvo. See his details on the forum elsewhere).

Here's the details I have left from Simon which matches what you were quoted for 13 pin ...These were early 2010 prices.

7 Pin Wiring Kit: [30756530]
Retail Price £19.93 / Our Price £16.34
Trailer Module: [30664974]
Retail Price £36.44 / Our Price £29.88

Or:
13 Pin Wiring Kit: [30756531]
Retail Price £84.20 / Our Price £69.05
Trailer Module: [30664974]
Retail Price £36.44 / Our Price £29.88

Don't forget that even though the Thule 909 requires a 13 pin you could get away with the 7 pin wiring loom if you buy a 13 pin to 7 pin adaptor - though to be honest probably better to get the 13 pin these days.

Thanks a lot. Am I correct to assume that if I am ordering the Volvo wiring kit, that I do not need any wiring kit from Westfalia, just the actual towbar? This is my first towbar (as you may have gathered ;-)

[XCF]

Correct - you don't need any wiring from Westfalia. You also don't need any SW download from Volvo if all you will put on the back is the bike carrier (all the SW does is disable the cars fog lights which is useful if you're towing a caravan in fog ).

The Volvo kit is pretty straight forward and plugs into the trailer module and then up to the Rear fuse panel in behind the left hand side boot trim.

You've got an exec - so some of the instructions will differ for you slightly (might make your connection to the rear panel simpler as the instructions state there is already a wire connected that I recall you can still connect to). Rear the start of this post to see that you don't need to remove the side trim unlike the Volvo instructions below will say...

Take a look here for the instructions that come with the Volvo wiring. ..

http://vccs.volvocars.se/accessories...ar=XC90%202011

The Volvo wiring comes with the 7/13 pin socket attached and silicon sealed so don't fit the wiring before the towbar is on the car as you need to feed the Volvo wiring in backwards from the spring down wiring connector holder on towbar (it doesn't have a cut out in it - so all the loom has to go backwards through this plate - it's a squeeze but it will go - does that make any sense at all!?)

Shout if you have other questions...

[Kwozzymodo]

Excellent write-up by ABC and info from other members. You have inspired me to get a towbar fitted. I have just ordered the Westfalia and wanted to clarify that there are two other bits that I need - a 'wiring kit (7-pin in my case) and a 'trailer module' (what is this bit?). If I get a Thule bike rack with built in light board, will I need this module?

[Ron_XC90]

You always need the trailer module, as it connects the trailer socket to the car wiring and prevents issues with the bulb monitoring system.
Note that some Thule racks need a 13 pin socket, however can be converted if you don't need 13 pin for anything else

[TruckbusUK]

Originally Posted by Kwozzymodo

Excellent write-up by ABC and info from other members. You have inspired me to get a towbar fitted. I have just ordered the Westfalia and wanted to clarify that there are two other bits that I need - a 'wiring kit (7-pin in my case) and a 'trailer module' (what is this bit?). If I get a Thule bike rack with built in light board, will I need this module?

Double check, dont assume, some Thule bike carriers have the 13pin euro plug and wiring, mine does hence I purchased the 13 pin electrics (Thule classic Pro 903) as the moulded 7 to 13 pin and 13 to 7 pin adapters (even the Thule 9901) are all fairly crap IMO and kept falling out, on my previous car I used the plug/cable/socket converters, much more robust and stayed put.

Hope it helps

[CSS-Enterprise]

Could anyone please advise:

Once the towbar is offered up to the bolts coming through from the boot, does it rest on the bolts, thus allowing you a free hand to put the washers and nuts on?

I'm trying to avoid having two of us under the car...me holding the towbar whilst the other person puts the nuts and bolts on.

Many thanks

[XCF]

One person under the car is fine once the collars are in place and bolts through.