C8 Electrics

[alden]

Hi all
wife's car has started to play up, it displays on dash that rear door is open, (no its shut [ ) rear interior door light stays on, thus central locking wont function. whilst driving the display continues to say rear door is open and central locking tries to activate.
Sometimes when it does lock, the alarm sounds to say the rear door is open
I took of door panel and the rear washer hose had come loose with signs of some water about but nothing excessive, dried up the residue etc.
Would resetting the ecu help?
Is it a relay?

[micky707]

There should be a microswitch around the door somewhere that has probably moved out of position, I dont know the C8 but on my Xsara the bonnet would show open when it was closed and the alarm would blip to say something is open. It was the switch in the bonnet catch that would slip down from its catch. Once reclipped it was fine again.

[alden]

Having just driven the car, it appears to be linked to the door safety mechanism, I.E when you set off it should lock up, however it tries to but doesn't, once you hit higher speeds it just shows the attention light on dash and displays the boot open warning.

[micky707]

Have you googled this, may be worth a try.

[alden]

Found this.......

When I turn left my Citroen C8 display says that one of the rear doors is open...
Claire Shipley, Nottinghamshire


Citroen C8 2004

When I turn left my Citroen C8`s display says that one of the rear doors is open. This causes the alarm to beep and the interior lights to come on! Please can anyone help?

Answers

I traced that problem to a damp connector block. Back left indicator cover (from inside) reach in and up about 8 inches. Turned out to be a leaky rear screen wash pipe connection, just above the electrical connector. As soon as I cleaned it, everything worked again. Symptoms were: Door open alert, can lock doors, sometimes cannot open tailgate. Good luck - Neil Allen from Hampshire

My rear door has just started doing this annoying fault. Had the car 3 years no issues, go away and miles from home and car doesn’t lock, tailgate door is locked (although rest of car open). Read a way to lock things up was to open it whilst the rear wiper is on. What I’m finding is, whilst it releases the rear door and you are able to lock the vehicle up, minutes later the wiper arm returns to its off position and the courtesy lights in boot area come on. These then stay on, car remains locked and eventually the car goes into economy mode! Most annoying and will be taking to someone with diagnostics kit to let me know if there’s something obvious. Nothing is damp/wet as suggested so no ideas but will post an answer IF I get one! Very frustrating!!!!! Stacey from Dorset


Submitted: 07/02/2013 15:05:59 | ID: 17891

[alden]

And this...
C8 Rear Lock Problem






Messages 1 to 3 of 3.







ianmw
Joined Dec 2006
2 posts



Hi, I've got an 03 Citroen C8. After using the rear screen washer, I found the washer pipe had popped off causing a leak into the boot space. This has been refitted and works fine but has left me with another fault. The onboard display sometimes shows that the boot is open ( when its not ) and the boot handle won't allow it to open unless the rear wiper is running. Once I get the boot open and closed again, all is fine until my next journey. Also when the display tells me the boot is open, the central locking won't lock the car.

This is my first post here so I hope I've described the fault correctly and any help would be gratefully appreciated.


Tuesday, 12 December 2006

Discussion Archived








ian
Joined Sep 2006
930 posts



there is an ecu in the drivers side rear quarter. when the pipe comes of it floods the ecu with water and causes all sorts of probs. worth checking multi plug for dampness or corrosion.

Tuesday, 12 December 2006

Discussion Archived








ianmw
Joined Dec 2006
2 posts



Thanks for your reply. I've found the plug and yes it looks wet. I've dried it out and the boot worked fine. Keeping my fingers crossed it stays working.
Thanks once again.


Wednesday, 13 December 2006

[micky707]

Hope that helps you out

[alden]

No joy on any of above . Had panels off and just disconnected and reconnected, have done a ECU reset but nothing car continues to insist on not locking up, and locks/unlocks whilst being driven.

[miked]

All the electrics to the door (power windows, locking etc) go through a set of spring loaded contacts on the front of the door which 'disconnect' from the car when the door slides back. I would have a look and make sure these contacts are clean and that the spring loaded fingers aren't sticking. My guess is that it uses one of these contacts to see if the door is open.

As you have found out, both sliding doors has an ECU. I don't know where it is but if water to rear washer can get to it then I guess it must be behind the panel you removed (assume this wasn't the door panel but a panel next to the back row of seats?). Now I don't know for certain, but I cant think of any reason why the passenger side would be different to the drivers side (unless they are 'addressed', which might confuse fault finding) so if you suspect the ECU you could swap them round and see if the fault moves.

[alden]

Hi
Thanx for that . I did clean off the contacts but only on the door pillars, never gave the spring loaded one a thought actually on the doors . possibly the circuit to the rear door passes the side doors. Ill Try anything at the mo

[miked]

Oops, sorry, stop. If the sliding doors are OK then ignore my advice completely. Your first post said rear door and I assumed rear side door. Start looking for a microswitch or tilt-switch.

[miked]

That reminded me, I needed to go out to swap the kid's seats back out of my xsara into the '807.

So, I had a play with the boot and I'd say it's a microswitch (somewhere). If I press the boot release on the outside the 2 low level interior lights come on and the tailgate cracks open a little bit. If I press the tailgate back to closed (without letting the mechanical latch completely engaging the door) the lights go out. release and lights on. So it can't be a tilt switch, and I can't see any plunger type switches anywhere (However it was dark) I'd say there must be a microswitch in the door lock itself. It's either that or the usual citroen/peugeot wires chaffed in the flexible rubber between car and door issue.

Forget what I said about ECU's and sliding doors. This sounds like a conventional door not shut switch problem.

[alden]

Hi

There is a micro switch in side door but all seams ok with it, it activates the motor etc, and door latches when closed.

[miked]

Alden,

Can you just confirm, because I may be misunderstanding the problem here if you are still looking at the side doors.

Is the issue you have with the tailgate?
Are the 2 rear side doors behaving normally?

I haven't had access to this forum today until now. Last night I assumed I had miss-read your OP and the problem you have is simply that the tailgate / boot door doesn't know when it is shut. I'm now slightly confused (more so than normal for me ). When I got home today I did a simple test to find where the tailgate closed switch is. I opened the tailgate to horizontal (low level boot area lights came on), and used a screwdriver shaft to close the latch in the bottom of the door. Boot lights went out, I was able to lock the car even though the tailgate was wide open.

That information might not help you if I haven't understood what is actually wrong with your car, but the switch which tells the car that the tailgate is closed is definitely in the latch. If the problem is that the car thinks the tailgate is open when it is shut, then either that switch or the wiring to it needs looked at. I already mentioned the wiring passes through a flexible rubber pipe between the car and the tailgate which would be what I would check first.

[miked]

Reading it back and thinking about it; I think I have misunderstood you again.

So, when you said:

micro switch in side door

Did you mean to say a microswitch inside the door (ie. the tailgate)?