Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

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napping
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by napping »

wheeler wrote:
30 Nov 2021, 16:57
What is your reg or VIN?
I’ll need to get a wiring diagram up, the question is what diagram do you start with?
VIN is VF7**************[VIN obfuscated, can be read by forum staff] - 2006 model. Thanks. It would be great to find a wiring diagram for the post 2005 models.
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by xantia_v6 »

If we assume a single point of failure, the failure of both sidelights and starter would imply something upstream of both. Can you upload both of those?
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by wheeler »

Here is the starter circuit.
trace the maxi fuse feeds from 4 & 5 up to the 2 pin grey at BSI. Check you have power at shunt fuse, fuses 8 & 11.
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C3 starter.jpg
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by napping »

wheeler wrote:
30 Nov 2021, 23:58
trace the maxi fuse feeds from 4 & 5 up to the 2 pin grey at BSI. Check you have power at shunt fuse, fuses 8 & 11.
Image
Yes, there's power to the shunt fuse, plus fuses 8 & 11.
I haven't checked the grey plug pins as I don't know how to drop this post-2005 BSI down to access the plugs! :? I'm sure it's easy but haven't worked it out!
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by wheeler »

The grey plug should be ok if the fuses are live.
Next are you getting battery live at pin 2 of the ignition switch?
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by napping »

wheeler wrote:
01 Dec 2021, 13:32
The grey plug should be ok if the fuses are live.
Next are you getting battery live at pin 2 of the ignition switch?
Although I can't easily get the plug off the ignition switch (some anti-theft? thing in the way) I have checked the ignitions wires and there is a live orange wire into the switch and when I twist the key the starter wire goes live too.
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by wheeler »

OK next checks.
Is Fuse 8 in the under bonnect fusebox live (at both sides) all the time?
Fuse 13 in under bonnet fusebox is it ignition switched live at both sides?
28 way grey connector on under bonnet fusebox do pins 19 & 26 have a good earth?
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by ozvtr »

Both permanent powers available at the BSI but it fails to wake up when the doors open??

Wheeler, are there any other earths for the BSI other than pin 6 of the 16 way BSI green connector? Usually the lay out for each of the ECUs are the same for each diagram. So I would say not (just one earth).

Both BSI and BSM have one common earth, ME30A??!! That's different to the MK1, BSI and BSM have 2 separate earths each!

I was wrong about the starter. MK2 different to MK1. Starter solenoid driven from a relay in the BSM. Without further evidence, relay seems to be commanded by the CAN BUS. No BSI, no CAN BUS, no start.

Ha, Ha! COMs has an earth which is separate to BSI, MC35. That explains the "beep". COMs is not receiving CAN info from BSI and is sad and lonely.

I bet there is no earth at the BSI. And if the problem is the chassis connection at ME30A that will take out the BSM as well!
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by napping »

wheeler wrote:
01 Dec 2021, 22:12
OK next checks.
Is Fuse 8 in the under bonnect fusebox live (at both sides) all the time?
Fuse 13 in under bonnet fusebox is it ignition switched live at both sides?
28 way grey connector on under bonnet fusebox do pins 19 & 26 have a good earth?
ozvtr wrote:
02 Dec 2021, 01:09
I bet there is no earth at the BSI. And if the problem is the chassis connection at ME30A that will take out the BSM as well!
Great work both!

That makes sense! Any idea where the ME30A will go to earth? Is it in the cabin close to the BSI or somewhere under the bonnet?
(I'll now check Fuse 8, 13 and try the earth for pins 19 & 26).
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by wheeler »

I can check earth locations for you but wont be till later this evening.
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by GiveMeABreak »

I'll save you the time Wheeler.

Image

-M000 battery earth
-MC10 front left earths
MC11
MC12
MC14
MC15
-MC20 front right earths
-MC30 front left earths (dashboard)
MC31
MC32
MC33
-MC34 centre console earths
MC35
-MC40 front right earths (dashboard)
-MC50 central cabin earths
-MC60 left rear earths
MC75
-MC70 right rear earths
-MM02 engine earth
Napping Install.PNG
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by ozvtr »

D'oh! There are parallel earths for the BSI and BSM at MC10 and MC32!! So now it's unlikely to be the earthing points, all three would need to fail.

FYI. The earths are behind the passenger kick panel. MC10 would be in the engine bay.
earth 022.jpg
It's looking more like the BSI connector or BSI.

Check for continuity between pin 6 of the 16 way green connector at the BSI and ground. Check for continuity between pin 8 of the 16 way green connector at the BSI and ground.

Check for continuity between pin 19 of the 28 way grey connector at the BSM and ground. Check for continuity between pin 26 of the 28 way grey connector at the BSM and ground.
Last edited by ozvtr on 02 Dec 2021, 12:56, edited 1 time in total.
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by GiveMeABreak »

The diagram I put up above is just the body earthing point locations.

MC30 is an earthing point on the body not a wire.
ME30A is the Earth from an ECU attached to the Body earthing point MC30, shown on the diagram below top left between the BSI and the Engine Fuse Box PSF1.


Image
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by ozvtr »

I must point out that the photo is of a 2005 C3 and equivalent to a MK1 C2 and not a Mk2 (the OPs vehicle). However while the labeling of the earth points may be different, the location would be the same. There is very little mechanical difference between the MK1 and MK2 (there are some but not relevant).
Of the 4 earthing points in the photo two have 2 wires connected, one has nothing attached to it and one has 1. I bet that's the way of delineating two earth wires at the one earth point? 'A' and not 'A'.

However that does not explain why that "point'" on the diagram is labeled 'ME' (if the others are labeled 'MC' and they too go to ECU's). Agreed, there are some points labeled 'MM' and 'M0' but I bet they do line up with the circuit diagrams. For example the engine ECU is bonded to the engine at the 'MM' earthing point. I believe either the circuit diagram should be marked MC30A or the earthing point should be labeled ME30. I prefer the former not the latter. This would not be the first time I have seen errors in the circuit diagrams.

Sorry, I edited my previous post while you posted yours but I don't think it changes anything. Apologies if it does.

Again this is all moot as I cant see parallel earths in different places becoming unserviceable at the same time. :(

Concentrate on the green connector at the BSI. If you have continuity to earth there, then the fault is in the BSI. I'm saying the fault is to do with the BSI because the interior light and ETC don't come on when you open the door but the BSI has power going to it.
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by GiveMeABreak »

The earthing point is labelled 'MC' that is the physical point on the bodywork. 'ME' is the actual wire, that's the difference in the naming.

So in the case of the OPs wiring diagram above, the Wire ME30A is attached to Earthing Point MC30.

This is because there can be other wiring connections with their own names going to the same earthing point (remember this is only the Engine Injection wiring diagram - there can be other dashboard harnesses and wires that use the same earthing point) so, there there would be confusion. This is why you need to differentiate between the wires and the earthing points.