Info - fog lights faulty and beeping

Hi, my C3 cachet (2008) - just bought - in first week, it beeped on starting and dash said 'info - faulty side light' (or something like that), but I checked all lights and all was fine.

Today, it keeps beeping every couple of mins while driving saying 'info- fog lights faulty'. It beeps again and again and again.

The lights seem fine - any idea what to check? Can I at least turn off the beeping?!

thanks in advance,

Sam

Hello

The beep is to warn you of the message on the screen. You can't turn it off without fixing the fault.

You said you checked the side light that was indicated in the warning message 'info- fog lights faulty' but in my experience this is often not done correctly.

I would double check the lamp in question, just change it for a new one if you are not sure and the beeping and message will stop.


If it doesn't, then at least you know you have a serious fault with the electrical/electronics/computer that will need some serious diagnostics.

C3driver52 wrote: ↑Wed Mar 24, 2021 11:40 am Hello

The beep is to earn you of the message on the screen. You can't turn it off without fixing the fault.

You said you checked the side light that was indicated in the warning message 'info- fog lights faulty' but in my experience this is often not done correctly.

I would double check the lamp in question, just change it for a new one if you are not sure and the beeping and message will stop.


If it doesn't, then at least you know you have a serious fault with the electrical/electronics/computer that will need some serious diagnostics.

So I checked the lights, they were fine, warning did not show the rest of yesterday. This morning I started the car up and it beeped, this time saying LH brake light faulty. It did it a couple of times and then stopped. So there is definitely an issue with the diagnostics - some kind of faulty connection? Where do I check to fix this? many thanks

This Citroen C3 lights faulty message fix topic may be your problem.

The way the car checks the lamps is by pulsing low voltage (probably 5V) across the lamp in question and measuring the current. If the current is below a nominal amount the car flags a failure. The current is normally so low that the lamp will not glow. If you use an LED style lamp in place of the standard incandescent lamp, it will typically throw up a failure because of the low current the LED normally consumes and some times the LED will glow dimly because the test current is enough to energize it.
The number one cause of these failures is corrosion on the bulb base. The corrosion reduces the current when the test voltage is applied but at 12V the lamps light up just fine.
I would pull the suspect lamps out (perhaps even all of them), clean the bulb bases and contacts with a plastic scourer.

The alternative is water ingress in the connectors of the BSM. The fuse box in the engine bay. But it seems strange that it's just affecting the lights if it's water ingress into the BSM.

Arfur has just posted a link to the bad earth thread. That will also do it.

Ozvtr wrote: ↑Thu Mar 25, 2021 8:57 am The way the car checks the lamps is by pulsing low voltage (probably 5V) across the lamp in question and measuring the current. If the current is below a nominal amount the car flags a failure. The current is normally so low that the lamp will not glow. If you use an LED style lamp in place of the standard incandescent lamp, it will typically throw up a failure because of the low current the LED normally consumes and some times the LED will glow dimly because the test current is enough to energize it.
The number one cause of these failures is corrosion on the bulb base. The corrosion reduces the current when the test voltage is applied but at 12V the lamps light up just fine.
I would pull the suspect lamps out (perhaps even all of them), clean the bulb bases and contacts with a plastic scourer.

The alternative is water ingress in the connectors of the BSM. The fuse box in the engine bay. But it seems strange that it's just affecting the lights if it's water ingress into the BSM.

Arfur has just posted a link to the bad earth thread. That will also do it.

Thanks - the other thread points to the rear light cluster. My faults have pointed all over the car - even when lamps not illuminated. And all lamps working fine. And for long times no fault is indicated at all. Could there be another, more central connection that I can check?

Arfur Dent wrote: ↑Thu Mar 25, 2021 8:46 am This Citroen C3 lights faulty message fix topic may be your problem.

Will all C3s have this problem - is there a way to tell if my specific model has this bad wiring or do I need to dismantle the lights etc? thanks

samuelodog wrote: ↑Thu Mar 25, 2021 9:58 am

Arfur Dent wrote: ↑Thu Mar 25, 2021 8:46 am This Citroen C3 lights faulty message fix topic may be your problem.

Will all C3s have this problem - is there a way to tell if my specific model has this bad wiring or do I need to dismantle the lights etc? thanks

No, all C3s don't have this problem.

It is not a model specific problem that I can see, but it does cover 2002-2009 cars.

You need to actually look for yourself if you want to see if your car is affected. There are plenty of pictures in that post that will help you along with that.

samuelodog wrote: ↑Thu Mar 25, 2021 9:55 am
Thanks - the other thread points to the rear light cluster. My faults have pointed all over the car - even when lamps not illuminated. And all lamps working fine. And for long times no fault is indicated at all. Could there be another, more central connection that I can check?

Think about it. When the display says "side lights" what is it saying? When it says "fog lights" what is it saying? You are fixating on the front fog lights and front side lights but what is it actually saying?There are fog lights in the rear cluster. When it says "side lights" does that include the tail lights? So far all of the faults you have named could be the rear light cluster. I'm not saying it is but it's a good possibility.

As I said the lights don't illuminate when tested by the system and it checks the lamps ALL the time!

To answer your question, possibly . But I don't have a circuit diagram for a facelift C3. You would have to ascertain which lamps it's complaining about and see if they have a common earth. But on the pre-facelift model there is a whole bunch of earths located behind and under the LH main beam assembly and they are associated with the lighting circuits.
But I would check the rear cluster first.
The BSI and BSM separately test the lighting for failures and report their findings. The testing circuits are integral to the BSI or BSM. This means replacing the BSI or BSM (depending on which module controls that particular lighting circuit) if the testing system is faulty.

OK, I took rear lights off, there doesn't seem to be any issues in the wiring, no burns etc. I took pics, please take a look and let me know if you spot anything. One blub on left looked a bit weird...