C5 X7 Towbar Wiring

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Jetjockey
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C5 X7 Towbar Wiring

Post by Jetjockey »

And finally.

Could I ask a favour please Marc. The previous owner of my C5 has just turned up on my doorstep with the missing locking tow hitch (Witter). Frankly I didn’t think he was going to deliver but....... now that he has I would like to use it.
I note it has a 7 pin socket and I would like to upgrade it to a 13 pin socket. Could you point me in the direction of the specific wiring diagram for my car, or failing that, the source of such a diagram (service manual etc). I don’t mind paying, I would just like to know where to get it. It appears that Haynes don’t make a manual for the 2008 onwards series III model.

Many thanks. Gerald.
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GiveMeABreak
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Re: Air con again!!

Post by GiveMeABreak »

Hi Gerald, Citroen do a conversion adapter, is this what you need?
966F2FDC-FF1A-4F76-91B5-D883E0D4D5BA.jpeg
Jetjockey
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Re: Air con again!!

Post by Jetjockey »

Hiya Marc, yes and no.

That adaptor is more of a halfway house. The 13 pin socket (when wired correctly), also includes a dedicated 12v auxiliary feed and can have a smart relay connected. I’m going to have to get into the wiring to do that.
I’m a fussy bugger!

Regards
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Re: Air con again!!

Post by GiveMeABreak »

They supply the wiring instructions for the Citroen harnesses, along with the specific PSA Relay unit that works with the vehicles ESP system - so do you have an aftermarket wiring harness or a Citroen one?

I have put up the info in a different post for the Citroen wiring kits here:

viewtopic.php?f=3&t=62025&start=45

There's about 4-5 pages with photos towards the end.

I can provide you with a wiring diagram for the rear lights if that is what you require too - let me know.
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Re: Air con again!!

Post by Jetjockey »

Thanks Marc.
I have a suspicion that it’s not factory fit, or even PSA for that matter. I’ve seen no indication of any connection with the ESP system. I’ll study that post now and look at the PSA relay, I would like it connected into the car system if possible.

Thanks
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Re: C5 X7 Towbar Wiring

Post by GiveMeABreak »

Gerald, here are a sequence of Wiring Diagrams for the C5 X7 Estate / Tourer. They are necessarily large as they are Vector graphics, so that they scale proportionally without losing detail / for printing.

Most of the equipment codes can be found here on our Wiki - the equipment numbers are in ascending order. E.g. 2615 on the last diagram, is in 'List of Components Section 2 (from 2300 to 6579)' on the Wiki Section for electrical components.

Here is the Wiki Link:

Wiki Link to Electrical Components

You may find that the vehicle does not have the BSR relay unit fitted - these are optional and purchased along with the wiring harnesses from Citroen. They are customised for the specific vehicle. They fit in the rear left hand side of the tailgate behind the trim panel. There is pre-wiring to plug into the relay unit there already. This saves further wiring up the vehicle. It also provides a fused supply for the lights and an additional AUX supply for electrical equipment. And lastly, it also interfaces with the vehicles stability system to disengage the rear parking sensors and to enable a special programme to be applied when towing. It looks like this:
Trailer Unit.PNG
Trailer Unit.PNG (92.01 KiB) Viewed 841 times
Brake Lights
Image

Hazards / Indicators
Image

Reversing Lights
Image

Side / Tail Lights
Image
Jetjockey
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C5 X7 towbar wiring 2

Post by Jetjockey »

Hello Marc.

Just a quick thank you and one more query.

First of all thank you for those diagrams, very very helpful indeed. The plot becomes clearer as I’ve now removed the LH rear boot trim and found an aftermarket interface fitted, bit of a gash job, but functional.

The interface is powered via a 15amp fuse which is taken rather messily from a connector in the rear compartment. It seems a rather robust oval two pin connector (only one pin fitted).
Would you have any idea what the current capacity of the harness wire feeding that connector pin?
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F64A9380-A829-4221-841E-CBBD06689911.jpeg
973768BD-DE1A-4D23-97FA-B9040F12FBDB.jpeg
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Re: C5 X7 Towbar Wiring

Post by GiveMeABreak »

I have to say Gerald, you're sounding a bit like Columbo now 'Just one more thing'.... :rofl2:

No worries. I suspect there is a good chance (80%) that the previous person has identified that oval plug as the port that the official Citroen BSR relay unit / fuse box plugs into. Have a look at this picture. This is from the official kit for a C4 Picasso, but if you look at the bottom centre, you can see the oval plug with the green connector in. That looks suspiciously like the one in your vehicle. So they have bodged it by taking the feed directly from the pin - not brilliant!
Gerald BSR.PNG
PS I have merged your new post with this thread to keep things together. Just tag any more related posts on the end of this topic. :)