Problem with brake lights

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nicu22dun
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Joined: 20 Dec 2019, 13:32

Problem with brake lights

Unread post by nicu22dun »

Hello everyone.
I want to share with you my story.
Today i wanted to place a secondary battery in the trunck for my subwoofer and i needed to take the cable from the main battery inside the car and The easiest road was exactly through the main jack under the "engine" of driver whiper. All good until i tried to GO through that jack with a hole made by a drill but unfortunately i could not make the hole straight and when I pulled back The drill, i saw copper and immediately knew that i touched some wires.
The problem is the next one.

First case, engine stopped all is ok, the horn intensity is ok, nothing strange but when I press The brake pedal, the lights do not light up, even with The key in before start position.

Second case, engine on, the lights still do not turn on when i press The brake pedal when The lights are OFF and when is night let's say, the brake lights stay always on and no response when I press the brake pedal and also when i hit The horn, it sounds strange and less powerfull than when the engine is off.

I have 2 posibilities, first one is to brake that plastic that isolates The exterior and The interior of The car to see exactly what wires i cut and The Second one is to know exactly what color is for brake lights wire and The horn and make a bypass.

For this Second posibility I need anybody help to tell ME how does those 2 wires look, what color they have so i know exactly what wire to cut and bypass.

The car is a Citroen c5 x7 tourer 2010 prefacelift 2.0hdi 163cp with hidraulic suspension.

Thank you.

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GiveMeABreak
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Re: Problem with brake lights

Unread post by GiveMeABreak »

It's very likely that you have drilled into a harness. The brake lights and horn may not be the only issue - there could be underlying problems, especially with the safety systems, making the vehicle dangerous.

There is also a possibility that you may have damaged the CAN data network wiring, so I think you need a very careful examination of the damage.

For a start, I'll need your VIN to look at the correct wiring diagram.

nicu22dun
Posts: 3
Joined: 20 Dec 2019, 13:32

Re: Problem with brake lights

Unread post by nicu22dun »

GiveMeABreak wrote:
14 Jun 2020, 10:33
It's very likely that you have drilled into a harness. The brake lights and horn may not be the only issue - there could be underlying problems, especially with the safety systems, making the vehicle dangerous.

There is also a possibility that you may have damaged the CAN data network wiring, so I think you need a very careful examination of the damage.

For a start, I'll need your VIN to look at the correct wiring diagram.
Of course here it is VF7**************[VIN obfuscated, can be read by forum staff]
Last edited by myglaren on 14 Jun 2020, 14:56, edited 1 time in total.
Reason: VIN edited to obscure it.

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GiveMeABreak
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Re: Problem with brake lights

Unread post by GiveMeABreak »

You missed a letter out, but I have it now..

So here is the brake circuit.

2630 is the rear left hand brake unit and 2635 is the right hand side.
2101 and 2100 are the brake lamp control wires and these go to the BSI at pins 15 & 15 in the 40 pin white connector block.

The Harness that carries these should be 46 HAB which both brake lamp clusters (2630 & 2635) would go into I think.

Image

Circuit Diagram Here:

Image

Harness Location / Routing
Image

The horn uses Harness 10 PR

nicu22dun
Posts: 3
Joined: 20 Dec 2019, 13:32

Re: Problem with brake lights

Unread post by nicu22dun »

Oh dear, thank you so much for this, I will take in consideration later when another issue strikes out. For now I managed to deal with it, the problem was in the pass from engine bay to passager bay, a few wires were half-cut let`s say. Now is all good and thank you a lot again for the best response.
Last edited by GiveMeABreak on 23 Jun 2020, 10:58, edited 1 time in total.
Reason: Removed Quote (no need to quote previous post)