Wiring diagram

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Billathome65
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Wiring diagram

Post by Billathome65 »

Looking to wire up a tow bar to my C3 2002 model but need wiring diagram to identify correct wires.

Anyone got a link to a good schematic?

Cheers also the tow bar is new but bought second hand ( no fitting instructions ) it has a 7 pin plug. Are the wires that go to the car lights normally wired into the plug universal IE. stop light say pin 1? the wire for the tow bar to lights just consists of one length of wire with a small box to sound when indicators are turned on off.

Ie been told that the C3 wiring for tow bars can be problematic and can damage the ECU if wired incorrectly is this true If so it's important that the schematic is a good one.

Cheers for any and all advice

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GiveMeABreak
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Re: Wiring diagram

Post by GiveMeABreak »

The wiring issues will be related to the multiplexed systems used in many cars (CAN / VAN or full CAN for example). Any attached electrical devices should be compatible with the car's wiring system, otherwise they can interfere with the multiplexed data signals being sent along certain wiring looms in the vehicle and may cause problems with the operation.

On some cars with an ESP system fitted, it is important that the system is notified when the vehicle is actually towing, so that it can alter the dynamics of the stability programme to take account of a trailer or caravan in the event of an incident. The more expensive tow bar electrics have additional electronics that let the ABS / ESP ECUs / BSI know this whenever the trailer / caravan electrics are plugged in to the towbar electric socket on the car. When unplugged, the ESP system reverts back to the normal programme.

Looking at your car specifically, you won't have ESP on your system.

Here is some information that you might find helpful on the different electric wiring options:
https://www.pfjones.co.uk/advice-centre ... trics.html

Billathome65
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Re: Wiring diagram

Post by Billathome65 »

Cheers for that info most useful Looking deeper into this it seems straight forwards with the information gathered.

I'm not exactly sure if it is CAN as the Tow system came off another 2002 C3 and there is no relay box with it just one long wire from plug to lights advice and guidance appreciated.

Assuming it's straight forwards wiring as it seems I was worried more about statements I've had about ECU damage?

However as the wires are not sending voltage back to the ECU but just sending to the light I can't see this being an issue? and as long as each step is checked after each wire has been attached once grounded it should in theory run fine especially with this being an early model?

Assuming I am correct i my thinking do the left and right hand indicator wires go to the same plug or would I need to run a wire from the left hand light separately?

I know I'm using lots of assumptions here and my thinking may be incorrect. Am I missing anything or have I figured this right?

Also as the kit fitted has a sounder how do the wires coming from this attach do they need to go to the same wiring for R/L to loom so I get the sound?
Last edited by Billathome65 on 14 Apr 2017, 12:25, edited 1 time in total.

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GiveMeABreak
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Re: Wiring diagram

Post by GiveMeABreak »

I can't help you with the specific kit Bill, but you would need separate wires from the LH and RH indicator lights to go to the dedicated sockets. I had my towbar and kit removed, so I don't have one now, but I'm sure someone here who has wired one up will be able to help you.

Billathome65
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Re: Wiring diagram

Post by Billathome65 »

Thanks buddy much appreciated Ive watched two videos on youtube by the same guy fitting a tow system on both cam and older vehicles IE 2003 cars and he recons the older versions are not requiring the relay box as he was just wiring into the loom on the older car.

Will see if any other members have wired the tow bar system in the 2002 /05 models as yu say

Bill

Billathome65
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Re: Wiring diagram

Post by Billathome65 »

OkK guys, been asking the question CAN or no can?

I sent the details to a mate of mine who runs a garage he checked with one of his suppliers and his supplier stated my car needs the relay box?

OK if It needs a relay box can I buy a kit that allows me to connect the box to the existing lighting plug at the lights rather than stripping and soldering the wires?

If anyone has any information on this I can pm my VIN so the correct kit can be identified.

It's the very first tow bar ive done and there is very little information on wiring the C3 2002

Cheers for any further advice

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GiveMeABreak
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Re: Wiring diagram

Post by GiveMeABreak »

Bill PM your VIN and I'll check the wiring systems in your C3 for the year.

Billathome65
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Re: Wiring diagram

Post by Billathome65 »

Cheers buddy VIN sent

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GiveMeABreak
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Re: Wiring diagram

Post by GiveMeABreak »

Nothing received as yet Bill. - Did you PM or email?

Billathome65
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Re: Wiring diagram

Post by Billathome65 »

Pm mate

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GiveMeABreak
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Re: Wiring diagram

Post by GiveMeABreak »

Nothing there! I know it's working as I've just had another PM from another member. Try again.

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Re: Wiring diagram

Post by Billathome65 »

My bad mate forgot to add subject PM sent

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GiveMeABreak
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Re: Wiring diagram

Post by GiveMeABreak »

Ok, it's finally come through Bill, give me a second or two.

Billathome65
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Re: Wiring diagram

Post by Billathome65 »

No probs mate.

Been a nightmare identifying this myself if it's not CAN then I know I dont have to mess about running a power lead from the battery.

If it is then if there is a kit out there that allows direct plug in from the lights saves the messing of cutting and soldering. Nice easy job when we get some sun :-)

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GiveMeABreak
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Re: Wiring diagram

Post by GiveMeABreak »

Sorry this has taken so long. As you might expect - nothing is simple as far as PSA vehicles go. It seems there are several combinations on the C3.
There are 4 multiplexed networks in use:
Comfort VAN
Body VAN 1 (for safety devices)
Body VAN 2
CAN

I've looked on the wiring diagrams and the vehicle does have CAN high and low wiring, so the answer is I cannot be certain from this, but I suspect that it won't be CAN for the lights.