C5 Tail Lights

[sparksie]

Hi all

A relation of a neighbour is coming to visit them this weekend.
Apparently the tail lights on their '08 C5 have recently packed up and their usual garage has tried and failed to fix them.
My neighbour has volunteered me to fix them, while the car is in the area.
My question is this... If a garage that has been looking after her for years cannot repair this, there must be something more than bulbs/fuses at fault. Is this going to be a multiplexed car, with some software issues?
Has anybody come across this before?
Thanks all
By the way, welcome back Jim...

[GiveMeABreak]

Yes all C5s are multiplexed. The X7 is a full CAN vehicle (and I'm assuming this is an X7, and not a late registered Mark II (facelift).

Assuming I'm correct, you'll need to ascertain which tail lights have gone as there are 2 lots. One on the combined Stop / Tail Bulb and a separate one. Here are the locations for a Saloon and a Tourer:

Just to make life simple - the bulbs are contained in 2 sections - the actual body wing and the others are in the boot lid (Saloon) or tailgate (Tourer).

Saloon	Tourer

I think it is safe to rule out an earth as both the left and right hand sidelights have separate earth points, so unlikely for these both to have a poor earth at the same time.

ALL front lighting is controlled by the Engine Bay Fuse Box, ALL rear lighting is controlled by the BSI.

Get ready with Diagbox as you'll probably need that to get a code.

[Sloppysod]

My neighbour, an electrician, spent a couple of hours yesterday trying to get his rear lights working again on his piccasso, I popped in and asked if he needed help. He explained had happened, started off just an indicator bulb, then stop, the tail. I convinced him to do a bsi reset. This fixed his problem, citroens get confused if you remove or fit a bulb with the ignition on.

[sparksie]

Oh JOY!
I'm not familiar enough with C5s to even ask the right questions.
I think I've seen this car outside the neighbour's house once, last year.
I only noticed because it brought the number of Citroens in the area up to two!
The neighbour's son tells me it has a magic steering wheel, by which he means the centre doesn't rotate with the rim.
Is that possible?
It's certainly true that, if it can be achieved, it will be found on a Citroen!
I guess I'm going to be trying to install Lexia on my "new" very second-hand laptop, then.

[GiveMeABreak]

Yes, fixed centre controls - so the actual steering wheel rotates but the whole centre unit remains static - it's designed to ensure the airbag always goes off at the optimal angle should it ever need to and secondly it means all the controls are in the same place - and no need for all that Carlos Fandango, finger-twisting contortionism when trying to adjust the volume using the steering wheel controls as you go round a 90 ° bend or a roundabout

[sparksie]

Wow!
I can't wait to get my hands on one of those in a scrappy.
If I'm to preserve my almost deity-like status in the neighbours' eyes, I'm going to have to figure this one out and, because of the relationship we have, it's going to have to go down to the advertising budget, so I hope I have more success with Lexia this time around.
I've never needed it on the Xantia and any Peugeot diagnostics I've ever needed to do have worked out ok with a generic code reader.
Wish me luck...

[GiveMeABreak]

Unfortunately this type are uniquely designed for the X7 Sparksie. A slightly different version was used on the C4s.

Don’t expect anything with a generic code reader to be honest, as if this is going to be more than a contact issue you’ll need to make sure your kit can read the BSI properly. There is no guarantee a fault code will be generated, but suspect areas will be the steering control unit under the steering wheel, or the BSI.

I would also try and manually switch the lighting stalk to side lights, then headlights and check the tail lights are not functional in any of these modes.

A daft question, but have you also checked the bulbs themselves? It wont be the first time I’ve seen duff bulbs used. A blast on the old multimeter should confirm and also check the lighting circuit for the tail lights is getting power.

The circuit just shows the connections to each earth left and right hand side and then the power to the BSI directly.

[sparksie]

Okay, well, as I have yet to see the car, or even speak with the owner, I have no idea what has been tried.
All I know is what my neighbour and his son have told me.
Apparently it spent a few days with her usual garage, who conceded defeat and told her to bring it to Citroen and to use the rear fog lights until she gets it fixed.
My neighbour doesn't understand electricity at all and regards anybody who does as a practitioner of the black arts.
Having occasionally succeeded where others have failed, he now regards me as the ultimate authority and recommends me to anybody with ANY sort of electrical problem, domestic, or automotive.
I've told him that modern cars are really more like computers with wheels and I'm not a white lab coat type of guy, but he still fully expects me to pull the rabbit out of the hat.
It's pretty stressful, trying to live up to expectations, but there's no denying my successes turn into further work, of a type I am comfortable with.
I use an old "OBDKey" and a multimeter for virtually everything and rarely ever need to farm stuff out, but I can feel the day when I can't do that approaching.
Full CANBUS equipped cars are finding their way to me more often, nowadays and I know I'm having good luck when I fix them.
I'll have to update, or retire, soon.
Or specialise in classic/vintage stuff, I suppose...

[sparksie]

Hi Marc, Stu, and everyone else
Thanks for the replies.
Events overtook us and I got a reprieve.
On her way over here, this lady had an uncomfortably close encounter with a 4WD Massey Ferguson.
A quick visual inspection revealed broken head and fog lights, cracked bumper, tread shaped dents on the leading edge of the bonnet and the o/s wing pushed back just enough to foul the driver's door and prevent it opening.
I can't open the bonnet until the insurance assessor gives the go ahead, so no opportunity to take any measurements, or try the BSI reset.
In the circumstances, I probably won't have any further dealings with the car until after it's been repaired, hopefully by somebody who knows their Citroens, as I no longer have a bodyshop and won't be looking for the job.
I did get to play with the steering wheel, which is the freakiest thing I've seen in ages.
Can't wait to take one apart and see how it works!

[GiveMeABreak]

Whoops! Well given the latest turn of events, I think the tail lights will be the least thing on their mind. I hope they were all ok and no injuries, the C5 X7 is quite solid.

Knowing how much you were looking forward to the job, are you sure you weren’t sticking pins into a model C5 and uttering curses?

[sparksie]

LOL
Actually, it seems like a very nice car and I think I'd have gotten to grips with it, with all the help I got on here.
I would prefer to learn about it on something I own, though.
These "favours" scare the living daylights out of me, because I still have all the risks of a proper job, with the added potential embarrassment, if I fail, but no tangible reward for success.
To be fair, I do get a lot of paid work through word of mouth, because of this neighbour bragging about me, but that's hard to quantify.
I think, if things improve a little, I may look out for one of those to play with. It seems a worthy successor to the Xantia.
I quite liked the early jelly mould C5, in much the same way I did the Sierra, but this one is a properly pretty car

[sparksie]

Hi all
I know this is a thread that should have fizzled out, but a freaky event has prompted me to revive it.
As I said earlier in the thread, my first encounter with an X7 was due to inoperative tail lights, which I did actually sort out by doing a BSI reset, thanks to you guys.
Today, I came up behind another one with no tail lights. I almost hit it, because I was blinded by oncoming headlights, but luckily so was the driver, so he braked and the sudden red glare, practically under my bonnet, alerted me.
I eventually caught his attention and got him to stop, so I could tell him. He was over here on holiday from the UK, travelling with somebody else, (possibly family) also driving a C5. It was bucketing rain, so I wasn't up for messing with batteries at the roadside, so he decided to call the other car and get them to drive behind him. A great idea, you would think, but when the other car arrived, incredibly, it had no tail lights either.
Just what is the deal with these cars?
That's 3 of them in a very short time.
All with absolutely nothing lit at the back, despite headlights being on, not even the number plate!
Indicators and rear fog lights all fine, so these two carried on with fog lights blazing.
Surely this can't be a coincidence, but equally surely, it can hardly be common, can it?
None of these drivers were aware they were in stealth mode, until outsiders told them.
I don't know how old the UK reg cars were, but the Irish one is 2008, which makes it an early one, I think.
Is this a known issue? Or perhaps something just emerging?
What, if anything, can be done about it?
I was saved today by an inconsiderate b4st4rd not dipping his lights, but if I had driven into the back of an unlit tourist, I would almost certainly have done enough damage to make proving it difficult, not to mention any potential injuries.
Scary stuff!

[sparksie]

...That's 3 of them in a very short time.

Or put another way, a 100% failure rate for all of this model I've ever had any dealings with!
How can such a failure mode even be possible, let alone at that frequency?
Surely, if the lighting circuit is going to be split, common sense dictates that it should be split side:side, not front:rear.
That way, should one circuit fail, there will be a noticeable drop in light output, from the driver's perspective.
The present setup is so dangerous.
Even my 1985 Volvo 7 series has a very obvious bulb failure indicator, so how is it acceptable, over 20 years later, for a high end car to be totally unlit at the rear without any way for the driver to know?

[bobins]

It's a good job we still have an annual MOT test over here to pick up such things as non-working rear lights. To think there were moves to make it a 2 yearly check

[myglaren]

When my son takes my C5 to work at 22:45 I watch him go and check that all the lights work as intended.
Saves me farting around in the cold