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 »

Just went to start checking earths..... Reconnected the battery....... The car burst into life and unlocked the deadlocks! :-D

I opened the door and the interior light came on - but just for a couple of seconds.
Then back to square one - everything was dead again! :(

This suggests to me that the BSI itself still works and the problem is more likely to be power, earths or signal to BSI wires - so just about anything!

As ozvtr says, back to pin by pin wire tracing.
Pablo
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by Pablo »

Not looking back through all the posts but......I guess you have tried a different battery? I've come across the odd few, particularly on trucks, which have had a broken connection under the post causing an intermittent connection.

Clutching at straws probably but worth a mention.
ozvtr
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by ozvtr »

napping wrote:
20 Dec 2021, 12:34
Just went to start checking earths..... Reconnected the battery....... The car burst into life and unlocked the deadlocks! :-D

I opened the door and the interior light came on - but just for a couple of seconds.
Then back to square one - everything was dead again! :(

This suggests to me that the BSI itself still works and the problem is more likely to be power, earths or signal to BSI wires - so just about anything!

As ozvtr says, back to pin by pin wire tracing.
Well this is good and bad news.

Good: it's not a permanent fault...it can be repaired!

Bad: you have to find it!

Is it cold there at the moment? Just a few potential things that could go wrong with the BSI and give these symptoms. Bad power regulator/semiconductor. They usually fail when they get hot/warm. Bad solder joint. Solder joint just makes contact until it warms up (current passing through it).

Although if it did this once before I doubt it's a semiconductor. They don't just start working again (er...usually).

Sounds like perhaps a point contact problem, or lack there of! Like a broken wire, bad connection or solder joint.

You could try pulling on the wiring and connectors?

Give the BSI a few good thumps!! LOL, that'll learn it!!
napping
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by napping »

Pablo wrote:
21 Dec 2021, 00:37
Not looking back through all the posts but......I guess you have tried a different battery?
I sent 12v to the starter solenoid and the engine turned over freely - confirming the battery is fine.
napping
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by napping »

ozvtr wrote:
21 Dec 2021, 09:41
Sounds like perhaps a point contact problem, or lack there of! Like a broken wire, bad connection or solder joint.
You could try pulling on the wiring and connectors?
Question: If there's a bad contact on the ECU pins could it cause the BSI to remain asleep?
I hear that the ECU plugs are prone to problems, especially for cars that aren't in daily use. The ECU plugs are very exposed and I suspect the car has been subjected to more than its fair share of condensation due to lack of use during the pandemic.
Hell Razor5543
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by Hell Razor5543 »

I wonder what would happen if you were to spray some contact cleaner into all of the plugs, and then unplug them and plug them back in several times? I have experienced a build-up of tarnish on the blades of a fuse that caused my rear wiper to go intermittent. Although I didn't use any contact cleaner, unplugging it and plugging it in several times cleaned the tarnish off, and the wiper behaved itself.
napping
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by napping »

Hell Razor5543 wrote:
21 Dec 2021, 19:45
I wonder what would happen if you were to spray some contact cleaner into all of the plugs, and then unplug them and plug them back in several times?
Worth a try! If I do one plug at a time, there's a chance I can find an offending plug :? I've tried pulling, pushing, wiggling and swearing at the wires - so hitting them with contact cleaner can't do any harm :)
Hell Razor5543
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by Hell Razor5543 »

But make sure to plug/unplug each one several times, as the action should help remove any dirt (ably assisted by the contact cleaner).
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xantia_v6
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by xantia_v6 »

My guess now would be that there is a faulty solder joint on one of the PCBs that handles the main feeds.

Either try another BSI, or dismantle and inspect carefully with a magnifying glass.
napping
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Re: Citroen C2 - dead electrics - No power to locks, interior light, ignition - everything dead

Post by napping »

xantia_v6 wrote:
21 Dec 2021, 21:00
My guess now would be that there is a faulty solder joint on one of the PCBs that handles the main feeds.
Either try another BSI, or dismantle and inspect carefully with a magnifying glass.
Ok - next plan of attack will be; double check earths , examine and clean each plug and its pins on the ECU and, if that doesn't work, consider opening up and separating the boards on the BSI for inspection (or get it bench tested!).