No one has any ideas?

 

my guestimate would be BPGA relay not regulating voltage correctly, but it could have additional different issues
Would help, if you'd post 6, 7, and 8'th Letter/digit of your VIN found through windscreen on your door sticker and/or registration document

 

I wonder if I bridge "always on side" of the BPGA to the "relay side", and car starts, would that poof BPGA is faulty?

Edit ^^^ in bold.

 

PEUGEOT 508 2.2 HDiF 200 DW12CTED4 (4HL) 2010 - Onwards

What DTC do you have... might help, even if temp codes to see the list. And know where to go hunting.
The noise is from twin brake switch and not suggesting it is in fault condition. But might start here, if guessing without DTC information.

Starting Circuits - Overview

2120

1032

PSF1

1031

PEUGEOT ALL MODELS WIRING DIAGRAMS - GENERAL (autoelectric.ru)
BSI Reset / Battery Disconnection / Reconnection - French Car Forum


Hope you find this useful

 

Other Information

 

These are the readouts from two days ago and from this morning. (Prints are numbered in the order I made them)
If there are no codes, that means I made the printout after I cleared the codes from the previous scan.
Printouts with the codes are right after I tried to start the car, but it wasn't successful.

I wasn't able to start the car in the last two days.

Now when I try, it just clicks once and resets back to ignition position, like the second video. Before, when this problem started, there was lot more happening. There were multiple clicks, gauges were going up and down like if electric power was going on and off in rapid succession.

 

This is a readout I made before I realized I can print to PDF. These were made even before the ones from the previous post.

 

I see this thread has been around for a few days so I am not sure if you still have a problem.

One thing I did notice in you Diagbox results is the engine was locked. If that's case the immobiliser is stopping the car from starting. This is likely to be related to the CAN-IS fault being reported. The CAN-IS is the main high speed CAN bus and links the engine ECU and BSI. In your first video in the no start condition the Tacho display behaved strangely which also suggests there was a communication problem on the CAN-IS bus.

It is also a bit odd that some ECUs are being reported as unconfigured. Have any parts such as the engine fuse box (BSM) been replaced in the past.

 

No, there wasn't anything electrically replaced since I bought the car.

 

There are three ECUs that are not configured. If they haven't been changed there may have been a power supply failure that wiped the configuration. The units are:
BSM - main engine compartment fuse box.
air-conditioning ECU
Driver's door module
It is unusual for the BSM to need configuring but it does need configuring on the 508. The other two devices may not be working properly is not configured. You can configure these ECUs using Diagbox. I suggest you see if you can find how to configure the BSM before doing anything else.

Looking through you Diagbox results I see that on several occasions the power steering ECU didn't have power (0V). I looked at wiring diagram for the power steering and I see relay 6 of the BSM provides power to the power steering. That relay is also involved with the immobiliser. When the car recognises the key it unlocks the engine ECU and releases the steering lock and relay 6 switches. I think there are two possible causes of your problem:
(i) Faulty engine fuse box (BSM)
(ii) Faulty steering lock
However, I noticed in one of original Diagbox results that the engine ECU was locked. This means the immobiliser has not unlocked the engine ECU. The steering lock is part of the immobiliser system on the 508 so I suspect the steering lock may be faulty. It is quite common for 508 steering locks to fail. The problem is you need the car's PIN to program a new lock and once coded it can't be transfer to another car.

I have attached 3 wiring diagrams and the engine fuse box (BSM / PSF1) fuse allocation document.

 

When I put the car in the on position, I can hear steering lock unlocking and locking back on when I switch off the car.
If I delete all the codes, turn the ignition to off and back on, scan for the codes, there are no codes. The codes reappear only alter I try to start the car in electricity cuts as seen in the video.
When this all started, and I was still able to start the car, I also scanned for codes and there were none. This makes me to believe, most of the codes are related to the power cut when trying to start the car.

I should also mention, that two days ago, when I unlock the drivers' door, wing mirrors didn't deploy and windscreen wipers went up and down once.

 

I not sure the fact that the steering lock motor working is enough to guarantee the lock is working properly. The lock gets its power from relay 6 in the BSM (engine fuse box). However, at some stage relay 6 needs to switch from powering the steering lock and connect power to several thing including the steering pump ECU. I know from another 508 with a steering lock problem relay 6 doesn't switch immediately the ignition is turned on. I not sure but it may switch when you try to start the engine.

If the steering lock is okay there could be a problem with the BSM itself. The fact that it is being reported as unconfigured is suspicious. As I suggest you should try to configure is using Diagbox.

The wiper and mirror problem is interesting and that may relate to BPGA (fuse box on the battery). This has an internal relay that controls power to a lot of ECUs including the mirrors and wipers. This relay often becomes intermittent.

I think you need to do a few voltage measurements. For example it would be worth checking the voltage at the BPGA fuses.

EDIT
Next time the power fails when you press the start button It would be worth checking if there is voltage at all the BPGA fuse. Some fuses have power all the time other are controlled by the BPGA's relay.

 

I assume the steering lock issue you reference was mine?

Configuring the BSM is straightforward. The one in my 508 now, was originally from a Citroen DS5 (same part number). It was mostly configured the same, the only difference being headlamp wipers from memory (obviously the 508 doesn't have them but they were configured as being present on the BSM)

Another point to add in relation to relay 6, I found that my original BSM was causing the steering lock issues (problems returned when I put the original back in and went away as soon as it was swapped back to the replacement), so I'm not sure if the relay switching was normal or not. I can check this when I next have the car.

Ian, did we also determine that the wiring diagram could have been wrong with regards to which fuses relay 6 actually switches?

 

I am not at home until the Monday so I can't test anything now.
Is it possible to run some tests using the Diagbox if the motor isn't running?

 

I am not at home until the Monday so I can't test anything now.
Is it possible to run some tests using the Diagbox if the motor isn't running?

Yes it quite common to collect live data. Some owners even drive with Diagbox running.

 

There was an YouTube vid on O'Rileys Autos channel that helped me with some intermittent issues (none so bad that the car wouldn't start, but mostly annoying gremlins).
I don't know if it's ok to link directly to the video here, but search for
"Citroen C4 Picasso Various Faults Gearbox ECU CAN communication Diagnostic Inspection", post date 15 Apr 2023

I found several furred up connections and after cleaning them up a bit, things were greatly improved. Maybe one day I'll do a proper job on it.

 

There was an YouTube vid on O'Rileys Autos channel that helped me with some intermittent issues (none so bad that the car wouldn't start, but mostly annoying gremlins).
I don't know if it's ok to link directly to the video here, but search for
"Citroen C4 Picasso Various Faults Gearbox ECU CAN communication Diagnostic Inspection", post date 15 Apr 2023

I found several furred up connections and after cleaning them up a bit, things were greatly improved. Maybe one day I'll do a proper job on it.

I found the video you were referring to see below. The part he was working on was the BPGA (item 1032 in the diagrams RedSector provided). The most common fault with these is the internal relay becomes intermittent. Some fuses are controlled by the relay other are not.

 

Hello!
I'm back and can test items if needed.
Is it possible BPGA relay is faulty and cuts electricity when I try to start the car.
Would this explain codes I get after I try to start it, and it fails to start?

BPGA relay is controlling power on fuses 3, 13, 9, 4, 11, ... There are also fuses on the back side of the BPGA.
Fuses 19, 2, 15, 5, 7 and two small fuses up/left of 19, have constant power.

Thanks

 

Your car has the older type of BPGA with a seperate relay. I have marked the relay in your photo. The way the BPGA usually works it when you unlock the car the relay closes and the rear view mirrors fold out. Once the relay closes it does not open again until several minutes after you lock the car.

If you want to bypass the relay I have put a link to a youtube video which may help you.

I have also attached a file that gives the function of the fuses.

 

One thing I forgot to say about the BPGA relay is that in many cases the relay becomes intermittent. If you are finding the fault is repeatable I think the cause is unlikely to be the BPGA relay.

 

Is it possible to test starter motor with Diagbox in the condition of my car and how? Same question for the battery.

 

One more observation.
When I tried to start the car, and it failed, I was able to hear a spark inside the ON/OFF button, if this means anything. It was quite noticeable.

 

There is a battery status monitor so you should be able to see the some details of the battery in Diagbox . Here is an example another forum member recently took. It is from a different car but it should give you an idea of what to look for. I don't know of any starter motor tests in Diagbox.

The results below reminded me: - I noticed in one of your Diagbox results your BSI shunt is in Park position it should be in the Customer position. The Park position is the predelivery position. The dealer changes it to the Customer position when they deliver the car. The BSI is your main cabin fuse box and there should be a grey fuse labeled SH. This is the shunt and it has two positions.

The spark in the ON/OFF switch sounds rather strange. The switch should only be switching low currents.

 

It's faulty 3 months old battery... Son of a b...
Thanks for trying to help me.

 

Good to hear you have found the problem. I had a battery that only lasted 12 months. It was fitted by a dealer so they replaced it under warrantee.

 

So this started two days ago.
This is video I made this morning. As you can see, car at first try started OK, but on the second try this happened video
Sometimes it also clicks rapidly without starting, of course.

Peugeot 508 SW 2.2 GT, 12/2011, 230000 km.
Car keyless opens/closes normally, door mirrors open normally.
Car battery is two months old and was charged over 4 hours yesterday, it was at 12.5V in the beginning and at 13V after.
Car alternator charges at 14V or similar at idle speed.
Diagbox shows many errors after this happens, but I presume, it's related to the failure to start the car and electricity cutting. All errors can be erased and when the car starts, it drives normally.
I did notice yesterday after the car started, and I went for a dive (it was dark outside), that low beams blinked for a split second a couple of times at the beginning, maybe 30 seconds on the road.

Any help would be appreciated.

PS
Maybe I hear things now, but I don't remember breaks sounded like this video (sound seems to come from the back of the car) or break "switch/relay" being so loud video

Now I haven’t read previous comments but watched your video, and mine did the same out of nowhere, aside from it warning that it went into safety mode for a while spontaneously, which I’ve understood can be a sign the BPGA box is living on borrowed time.

for me the solution was a new BPGA box and it’s worked perfectly since then

 

I had a guy from AA come to tow the car to the service. He had a booster pack with him and asked if we should try to start the car with it.
Sure, why not... We did 3 attempts when I tried to start the car using just my battery and fail, then I was able to start the car after he hooked a booster to the car.

He said it's battery.
I will replace it today under warranty.

 

I had a guy from AA come to tow the car to the service. He had a booster pack with him and asked if we should try to start the car with it.
Sure, why not... We did 3 attempts when I tried to start the car using just my battery and fail, then I was able to start the car after he hooked a booster to the car.

He said it's battery.
I will replace it today under warranty.

Hope it fixes it, a lot cheaper than a BPGA box 😁