C4 Grand Picasso Electrical Issues (Poss BPGA?)

[Mumbus2025]

Hi All,

Firstly, apologies if I'm going over old ground here, I found the forum through a Google search of the issues we have and the best fit I could find was a post made here back in 2023 (viewtopic.php?t=74049). As the error codes etc. did not extend to the same scale as we're experiencing, I thought I'd be best to create a new topic and seek some advice.

Our 2016 Citroen C4 Grand Picasso (B78) 2.0 Diesel (AHX) has developed some dreaded electrical gremlins

Quick TL:DR as this post is likely to be quite long...
- Battery changed in January 2025.
- Amber warning 'Electrical Fault: Please Have The Vehicle Repaired' appeared shortly after changing the battery.
- Issue persisted over next weeks, until the car completely died after a weekend of no use. Showed all sorts of warnings, including engine fault, air bags, parking brake etc.
- Jump started and continued to use the car daily, no issues outside of initial warning.
- Car died again whilst on the drive awaiting a water pump replacement (non-related issue), took a few attempts to jump start.
- Battery test showed charging to 14V, discharge test showed that it dropped to 9V immediately but not below.
- Battery changed again, solved all issues short term but amber electrical warning reappeared the same day.
- Completed a BSI reset, worked initially but same error appeared a few hours later.
- Diagnostics showed a total of 87(!!!) error codes.
- Car continues to run, everything is functioning.
- Suspect a possible BPGA issue, hoping for some advice to confirm or rule out

Full details below, I can try and expand on any parts that may hold some relevance.

I changed the battery back in January 2025 as the old battery was >5 years old, start stop no longer functioning etc.

Pretty soon after changing the battery, the warning 'Electrical Fault: Please Have The Vehicle Repaired' appeared on the head unit. The car ran fine and everything was functioning as normal. my wife drives the car daily for the school run etc. A few weeks later, the car died on the drive after a weekend not being used. On attempted start up, a load of different warnings came up, including 'Engine fault: Stop the vehicle', 'Parking brake fault: Have the vehicle repaired' and 'Air bag(s) or pretensioning seat belt(s) fault. I jump started the car, it ran fine and only had the initial amber electrical fault warning. After each start up and when indicating right for the first time and new amber warning appeared ('Check direction indicators'). This persisted over the next weeks, but everything worked and the car was generally okay.

A couple of weeks ago the water pump failed (non-related, was leaking) so the car was OTR whilst we waited to get it into a local garage. On the morning of, the car was completely dead again. Couldn't jump start using a power pack, but managed to get it going using another car after a few attempts. Got it to the garage where they had no issues starting it over the next couple of days to complete the repairs. They tested the battery for me, came back as charging to 14v and on the discharge test dropping to 9V immediately but not dropping below. As the battery was under warranty, it was changed again. The errors stopped immediately after changing the battery but reappeared later the same day. I carried out a BSI reset and the same happened, issues resolved immediately but reappeared later the same day.

Took it back to a garage this morning, they are not electrical specialists but ran the diagnostics and returned a total of 87(!!!) error codes. These included engine management (x1 code), Airbag (x6 codes), Battery Charge Status Unit (x4), BSI (x4), COMM switch (x2), Door Control Pad (x7), Electric Power Steering (x4), Electronic Key Reader (x2), Engine Relay Unit (x4), Hands Free Access Module (x3), Hands Full Access ECU (Right Side or Rear) (x4), Instrument Panel (x7), Motorized Boot Unit (x9), Parking Aid (x12), Rain/Sunlight Sensor (x5), Reversible Seat Belt Inertia Reel (LH) (x3), Reversible Seat Belt Inertia Reel (RH) (x3), Right Hand Windscreen Wiper Motor (x3) and Supply Protection and Management Unit (x4). Everything that I can readily test is still functioning as normal.

After reading the thread that I linked above, I suspect it could be an issue with the BPGA but I just wanted to seek some advice before I bite the bullet and change it or go to an electrical specialist... the part is around £200 so in my mind it's worth a go before I subject myself to a hefty diagnostics and repair bill.

Has anyone had a similar issue that they've managed to resolve? Any input is deeply appreciated!

Thanks,

Scott

[Nick_UK]

I am complete novice compared to the others on this forum, but from what I have seen in some posts, other things to check are:
- whether battery connections are tight
- whether battery is adequately charged (note that city trips do not charge the battery enough, I have this issue on my C4GP whereby low RPM trips leave the battery with approximately 30% state of charge, because the alternator does not kick in properly below 1600 RPM -- see here: viewtopic.php?p=840966#p840966)
- whether alternator is producing enough output (same link as above)

[Mumbus2025]

Thank you - will have a good look at the connections this afternoon. The garage seemed to think the alternator was okay, although I don't know if they tested the output (it's definitely working to some extent)

[Mumbus2025]

I just wanted to update this with a conclusion for anyone else with a similar issue. After living with the issue for a couple of months I got round to changing the BPGA unit and all seems well.

There are plenty of videos with instruction on how to change the unit. I took plenty of photos before starting but in the end I found it easy to replace one cable at a time to minimise the chance of getting any mixed up.

Performed a BSI reset after changing it just to make sure, turned over first time and no warning lights at all. Hopefully it’s the end of the electrical gremlins for now.

[TC542]

Hi . . .
I also posted an issue that was related to the BPGA . . !! . . (I just updated my post . . .)
I resolved it by cleaning all the connections/fuses. . . .Saved me some pennies. . . Worth a try should it happen to anybody else.

[TC542]

Hi all . .again . . .
Maybe not sorted . . had it fail again . . .
I have the 'BPGA JL01 E1065591-1000' unit . . . (I presume a very early unit . . .)
Is there an updated version that fits my car . . . .e.g. JL04 . . JL06 . . .?
Regards . . .

[TC542]

Hi All . .again . . .
I decided to bite the bullet and buy a 'New' BPGA 'JL01' unit from eBay . . . (Needed the 'JL01' due to the 'Stop/Start' feature . . )
It arrived from the seller in a tatty cardboard box! . .Not a manufacturers box . ?? . . Also, there were no screws that should secure the covering panels . .??
I fitted it, but all hell let loose . . Electrical warnings! . . Indicators flashing fast with a warning! . . . SERVICE light 'ON', etc. . . . .
But at least the wing mirrors opened on unlocking and the engine started. But i decided to remove it and put back my original.

(I sent the 'New' unit back and got my money back via eBay . . .The seller tried to pay only half . . stating that I had damaged the 'New' unit, showing a slight blemish on one of the covers . . Luckily, I had a picture of the original eBay listing and zoomed in to the blemish that was already there . . !!!!! . . I wonder if they have tried this before . . .??!!. . . . . . )

During replacement, I fitted 2 cables to the central 80A and 60A wiring connectors fitted with quick connectors, so that if I had the totally dead car . . i.e. Doros would unlock, but no 'Start' button functions and the car not starting . . At least I could join the 2 cables, the wing mirrors would come out and be able to start the car. . . Eureka!

I then proceeded to complete a few procedures . . .
-Using the OBD Diagnostic Unit . . Clear all the Error codes.
-Reset the 'Factory setting' information using the operation panel.
-Complete a BSI reset procedure.
Using the OBD Diagnostic Unit . . Clear all the Error codes again.

I then seperated my 'special ' connectors . . . Since then my car has been running fine. No dead car. . . .
Haven't had to use the special connectors since the above . . .So think the BPGA unit was OK after all . .

I will of course update should the issue arise again.

[mickthemaverick]

Just a short addendum to the above. When you get this sort of multi electrical issues make a point of checking the various earth connections around the vehicle as well as the main battery connections. They can produce weird and wonderful fault collections if corrosion has set in!

[TC542]

Good point! . . . Good advice . .
I had previously checked/reset various earth/grounding points aswell as the fuse connections on the BPGA.

[TC542]

Mornin' . . Had to use my 'Get out of jail free' card again this morning . . (Please see pictures ). . Doors unlocked, but, mirrors didn't open out, no 'Start' button functions at all, no window winders,etc.
Connected my 'special' BPGA wires and all working.
Cleared errors . . The 'Service' light was still on, but reset by turningvon the headlights+FOG LIGHTS . . This is what cleared the service light . . ??!!
Main thing is that this link gets me out of trouble . . Works for me . .

[Uncle Tom Cobley]

Sorry resurrecting this slightly older thread.
I have been having the same problems on my 2016 1.6 diesel C4 Picasso Grand.
The BSI reset seems to keep the Gremlins at bay for around a week give or take a day.
However I have it booked into a Citroen main dealer this Tuesday for full diagnostics and a possible new BPGA unit after a local independent garage plugged into their diagnostics and discovered the B1624 fault code was showing alongside a few other weird faults such as blocked DPF filter and open circuit on oil pump , however they said they could not undertake the work as it had to be done by the main dealer or a specialist as the BPGA must be recoded to the specific vehicle and only these people usually have the software to do it, they didn’t charge me for the diagnostics which was nice as it should have been £60 ,however the cost of diagnostics and replacing the unit by the MD will be an eye watering £1100 !!
Just wondering if this maybe the problem with your BPGA unit ?
Oh! BTW I can get a OEM unit online for £290 but the MD will not fit it , they only apparently fit parts supplied by themselves.

[PaulC5]

The dealer will not fit parts supplied by others since they have to guarantee the work but would not be able to guarantee the parts. If it went wrong, all they would guarantee is the labour which makes any claims complicated.

[TC542]

If you decide to do it yourself . . Then ensure you get EXACTLY the same unit as you currently have . . i.e. 'JL01' . . 'JL06' . . etc. (Don't be fobbed of with . "These are compatible . . " . . !!)
Easy enough to change yourself . . No programming needed . . Maybe 'BSI' reset and error codes cleared.
(Make sure 'earthing'grounding points/cables are of good status . . )
Hope this helps . .
Hope this helps . .

[Uncle Tom Cobley]

@TC542
Yes thanks for that unfortunately I’m a little too long in the tooth for car mechanicals these days.
Out of curiosity what are the two “special wires” you use ? Has fitting the replacement BPGA unit not entirely solved your problems? Also I’m getting a little confused as the MD and two highly respected local independent garages have all said it must be reprogrammed to the vehicle and therefore the two independents couldn’t do the work ? Are you saying that this isn’t the case ? Not disbelieving you by any means just curious.
I have mine booked in for diagnostics first and I am hoping for a little fortune for once but I am the sort that if I won a luxury cruise in a star raffle it would of been on the Titanic
Reading various topics online I am sure as was pointed out to me in another thread ,that it is the BPGA unit that is going uptown.

[TC542]

Hi Uncle Tom Cobley . . I did finally succumb to buying the BPGA unit of eBay . . Correct type 'JL01' for my Exclusive+.
Just swapped, then BSI reset and cleared errors. No programming.
I decided to change due to getting an error on my replaced 'Adblue' tank . . !! . . '700 mile' warning!!
After changing BPGA I did not need to reset the 'UREA' ECU . . It cleared after the replacement.
Do not forget to extract the small fuse(s) and fit them into your replacement BPGA unit.

The 2 wires that I fitted to my faulty BPGA were fitted between the middle 2 fuses on the front side fusesof the unit . . See attached picture

Hope this helps . .