DS5 Circuit Fault

[DropThePuck]

Hello. Thank you for letting me join the forum.
I have a 2016 DS5 that has recently started showing the Circuit Fault error message with a graphic of the battery. Went to local garage who said battery had 5% health left, so replaced the battery with new 096 AGM.
Fault still appearing at ignition, but car starts and runs fine, including stop/start, apart from the service light staying on. Plugging into OBD2 reader shows no faults.
I think previous owner may have had issues, as glove box fuse area is a mess, and the insulation by the battery in the engine compartment looks a bit "abused".
So, does anyone have any thoughts on this? I am thinking possibly the battery management panel on top of the battery. I have removed, cleaned and replaced all fuses on this along with the connectors going to it. It looks like a relay on the front of it that does not click, so perhaps that? I have a "platinum" extended warranty, but no one seems interested to take it on.
Just a bit frustrated.
Many thanks.

[GiveMeABreak]

Sometimes the electrical circuit specifically the Battery Charge Status Unit, can take a few hours to register the new battery and its health status.

If you can leave the car locked and uninterrupted (i.e. don't unlock it again) for 2-3 hours as it generally needs this amount of time for the Stop Start systems to calibrate when a new battery is replaced / to register the new battery and start operation again (assuming all the other factors are pre-requisites are present).

If there is a fault your generic OBD II reader won't cut the mustard with these cars. it need a proper diagnostic tool like Diagbox to be able to read the manufacturer-specific faults that general OBD II code readers can't do.

[DropThePuck]

Thanks for your response. The battery was fitted two weeks ago, waiting about 45 mins after reconnecting before restarting. I have disconnected the battery a couple of times since, but cannot be certain that I waited 3 hours after reconnecting.
Would a disconnect for 30 mins, followed by an overnight wait be a good idea? The car was never programmed to say it has a new battery two weeks ago. I had to do that with my old BMW, but read not necessary with the 5.
Many thanks.

[wheeler]

What is the red/black wire for in the fuse box (2nd pic)?
Doesn't look original.

[DropThePuck]

What is the red/black wire for in the fuse box (2nd pic)?
Doesn't look original.

That shouldn't be there. I had hardwired my dashcam into the fusebox with a saddle connector. I had just disconnected it to see if that was causing the problem.

[Juliet]

Did u manage to fix this?

[DropThePuck]

I ended up taking to a Citroen specialist garage. They had to order the battery management unit that sits on top of the battery. It cost about £700 to diagnose, supply and fit. After a lot of arguing, my extended warranty company reimbursed me for a portion of the cost.
I now have other issues with the car relating to emissions that have put the car into limp mode a few times. I took the car to the dealer a few weeks back for this, and they couldn't see me for two weeks as they had no technicians!

[Juliet]

Oh god!
My car broke down other day and wouldn’t start, RAC said it’s crankshaft sensor, so took it garage and had it done but they said I needed a new battery as it was low voltage, so had a new battery on, got the car back and has service light on and that fault, showing a p1351 on my little diagnostic machine, so cleared it off but it’s still on. More annoying because it weren’t on before, only had the car 7 weeks and the warranty doesn’t cover it fuming .

[GiveMeABreak]

P1351 is nothing to panic about. It's a common fault code on all HDi engines and relates to a fault on the pre-postheating relay circuit, where the glow plug relay is controlled but the plugs are not controlled or responding.

Normally HDi engines don't need glow plugs to start unless in really freezing conditions, but the plugs are used by the engine management system in post-heating situations, for example to assist with regeneration of the particle filter in order to increase combustion temperature momentarily. So no need to panic on that front for now.

[Juliet]

Thank you makes me feel better, was contemplating just getting rid of it .

[DropThePuck]

Oh god!
My car broke down other day and wouldn’t start, RAC said it’s crankshaft sensor, so took it garage and had it done but they said I needed a new battery as it was low voltage, so had a new battery on, got the car back and has service light on and that fault, showing a p1351 on my little diagnostic machine, so cleared it off but it’s still on. More annoying because it weren’t on before, only had the car 7 weeks and the warranty doesn’t cover it fuming .

Sounds like you have something different to mine. I am sure my car was made on a Friday afternoon. Every time I start it up, I wonder if I am going to make it to my destination. I have broken down 5 times in 10 months of ownership.

[Citroenmonamor]

Similar fault on mine...

[Citroenmonamor]

Think of replacing the battery management unit

[PaulC5]

We had a C4 1.6 hdi that was not accelerating as quick as usual. It was still under the 3 year warranty so took it to the Citroen dealer. A diagnostic came up with a U code which showed a fault with the fuse box mounted on top of the battery so they replaced it and the problem went. I would not want to replace this first without doing the diagnostic since it could be a waste of money and the fault could remain if it was something else.

[PontyAl]

I have a ds ds5 2.0 bhdi auto, the last 3 years I have had the engine fault, needs repair warning and limp mode coming up, not that often and only as the ambient temperature drops as we go into autumn. It then happens Maybe 2-3 times through the winter months. Obd2 kit won't find it and apparently the battery management fuse box is on 8-12 months back order and around £500. I don't want to order it without confirmation but the fault disappears each time I switch off and back on so dealers havesaid it wont be in the memory. I've tried bsi resets which seem to alleviate it for a while but it keeps popping back up. I've had the correct Bosh replacement battery fitted last January but its just come up again now (October). Very annoying. It's a beautiful comfortable and I don't want to get rid of it but it's frustrating.