Need help solving C3 hazard switch & central lock function

Hi.

I have some strange problem with hazard switch & central lock buttons functionality (please see pictures below). They ceased to work properly and since then could not switch on when you press on them. The only option to make them work is to wait 3 minutes when all electric devices switched off and the car enters into ECO power save mode. Then buttons works only for once, because after the car woken up from ECO mode the button stop to work. To add more trouble if hazard light pressed in ECO mode it starts to work however you can't switch off it with the hazard button after the car woken up. To switch it off I need disconnect the battery and reconnect it, wait 3 minutes and then press the hazard button via open window.

More details:

Central locking working all the time from key fob, but not from the salon. So at the moment I more worried to regain normal functionality of hazard switch.
Until now I have exchanged hazard switch with new one with no luck and checked all fuses on the BSI unit (located under gloves box) and another set of fuses under bonnet (all fuses came all good). Disconnected and connected back all plugs in sockets on BSI unit, fuse box under bonnet. Still the same problem.

I would be grateful if someone could shed the light on my problem and help me resolve it. Also I would like to understand what kind of electrical signal makes to switch on/off the hazard light. I mean if this process driven by positive, ground or other type of signal. So maybe someone could provide the hazard button 3 pin outs description as per pictures below. There are 3 cables going out (orange, green, green/yellow) and I would like to know where they are connected to. Maybe there some loose ground somewhere or something similar. So I can check it properly with multimeter.
Would be great if some one have C3 electric schematics diagram and could send to me please.

I would really appreciate any input from fellow Citroen forum users.

Thank you for taking time to read my message.

Not much information I'm afraid, but the diagrams I've looked at suggest that both the switches you're having problems with are connected to the instrument panel. Other than checking wiring and connectors in that area I'm not sure what else you can do without access to fault code reading equipment.

Hi C3 Guru.

As you have access to diagrams please could you tell me what kind of signal should be present on each pinout for both switches. Parts of schematics for these areas would be great help. So I can trace then all grounds and voltages up to instrumental cluster panel. I would like to try that before I go for last resort buying Lexia 3 adaptor with software.

Thank you.

citron wrote:Also I would like to understand what kind of electrical signal makes to switch on/off the hazard light.

The switch has a ground connection and when activated the switch grounds (pin 5) the wire on pin 4 of the plug (295 Pink). Pin 1 is for the illumination inside the switch and shares the common ground (pin 5).

The diagram that shows this is in the Haynes manual for the C3. But, that's about it for the hazard light as the wiring disappears into the 'instrument panel'.

Hi everyone

Missing Lincs, now I got the lexia-type interface. Could you please indicate what I should check first with diagnostic interface and what software better to use. My interface came with DiagBox. Do I need pp2000 as well?


C3CAR thanks for help with pin-outs for switch. Up to now I checked the ground (all good) and even tried to substitute the another ground connection from another source and it didn't make any difference.

Signal contacts from button connected into the instrument panel. Any suggestions?

Regards

Diagbox should be fine. I find it's more a case of what you can get to run on your computer, none of the Citroen software I have seems to like 64-bit Windows, so I have an old laptop running XP-32 bit in virtual mode under a Windows 7 system, which runs Lexia.

When you get your interface and software connected to your car you're looking for error codes. I would look at each module as you don't really know where the problem is. You will probably find a few codes from things long gone, and it's possible, there may not be anything relating to your switch problem.

Hi Missing Lincs

I have checked with Lexia software and looks like there is no error code related to above mentioned problems. I only found few permanent error codes: Pre-Post heating relay circuit coherence and Remote fault: pictures attached.

I was unable to clear the error codes as the interface displays a error message when I try (see picture 3).

Any ideas why is happens?

As signal cables from malfunction buttons goes into instrument cluster panel I'm looking now to buy a used panel off the ebay. The panels offered on ebay comes with both P9645994280 and 9645994280. Are they compatible?
My one is P9645994280 on 2004 1.4 HDI C3.

Another aspect is if there any way to copy old data (mileage, etc) from old speedometer to new one? Is there anything I need to take into account before I start?

Cheers

citron wrote:I was unable to clear the error codes as the interface displays a error message when I try (see picture 3).

Any ideas why is happens?

Its not normal for this to happen, do you have the latest version of lexia/diagbox that your interface can handle? It may be due to old versions of the software.

citron wrote:n ebay comes with both P9645994280 and 9645994280. Are they compatible?
My one is P9645994280 on 2004 1.4 HDI C3.

Usually they are compatible, although the BSI may need an update, but that's covered by Lexia.

citron wrote:Another aspect is if there any way to copy old data (mileage, etc) from old speedometer to new one? Is there anything I need to take into account before I start?

Mileage is not easy as its protected and copied in the BSI. Mileage will usually be updated to the highest of the 2 that are present and its not a lexia job (that I have yet found) to change.




Faulty controls or wiring/connectors?



easy to ignore this for now.



Update lexia software? Poor connection on laptop or diag socket?



You can now use your Lexia to read the presence of signals from the various switches you want to test.

Bit of a stab in the dark guess but ... I'm thinking that your steering volume control fault might be the cause of your original button problem. The only fault that Lexia can detect is a short circuit on the switch, given that the same module reads all the switches, I just wonder if the buttons share an interface and having a switch permanently on is preventing it from reading the other switches or transmitting data from them?

Like I say, long shot punt but just try disconnecting the steering wheel audio controls if you can do this easily?

Hi everyone.

Missing Lincs, your "stab in the dark" proved to be absolutely fantastic guess. I have removed audio control unit near steering wheel and it cured the problem. Now both buttons hazard and salon central locking works absolutely flawlessly at any time.

The culprit is in the picture .


So now I need to source similar unit and that set!

Thanks to everyone for help and contribution!

Regards.