Citroen Picasso B78 Lexia needed.. Airbag light

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GiveMeABreak
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by GiveMeABreak »

Itchigo55 wrote:
21 Jun 2019, 19:35
Oh for context it's a C4 Picasso 2014 exclusive+. So the ignition advice for disconnecting the battery wouldn't work (keyless), oh and I can't get to the negative terminal, only positive.
I've been meaning to do this for some time - so the procedure has been updated to account for Stop Start / Keyless Entry Vehicles:

BSI Rest / Battery Disconnect / Reconnect Procedure

If you can only access the positive, then that's fine, use that.
Hell Razor5543
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by Hell Razor5543 »

My equipment is up to v7.15 (as it is a full B chipset), but I have been able to enable the DRLs on a 2015 C5 (and allow a C3 to recognise a CD autochanger, but I cannot remember the age). I couldn't post in the battery procedure, as it is locked.
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by Itchigo55 »

Wow, you boys are super efficient! Could be overtaking the Mini and VAG forums as my favourite =D> =D>
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by GiveMeABreak »

Hell Razor5543 wrote:
21 Jun 2019, 20:45
My equipment is up to v7.15 (as it is a full B chipset), but I have been able to enable the DRLs on a 2015 C5 (and allow a C3 to recognise a CD autochanger, but I cannot remember the age). I couldn't post in the battery procedure, as it is locked.
Hmmm, that may be a problem with the Picasso given the different kit - the C5 was finishing its run about then.
Also, I'm concerned about errors on the previous version that were corrected in 7.16 for all vehicles regarding BSI fault codes missing.

I've put the change logs up on the wiki here, but until I get the VIN I can't tell exactly what engine ECU he has....

https://frenchcarforum.co.uk/wiki/Diagb ... 9/7.06_On)
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by GiveMeABreak »

Itchigo55 wrote:
21 Jun 2019, 20:49
Wow, you boys are super efficient! Could be overtaking the Mini and VAG forums as my favourite =D> =D>
Really need the VIN as I can't determine exact kit you have. Post it here or put your reg up if easier (I'll mask the reg)
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by Itchigo55 »

Thanks, reg is *******
Last edited by GiveMeABreak on 22 Jun 2019, 10:58, edited 1 time in total.
Reason: Reg Masked
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by GiveMeABreak »

Itchigo55 wrote:
21 Jun 2019, 22:05
Thanks, reg is ******
That reg is not working - can you double check it is correct?
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by GiveMeABreak »

@ James - I realised what you are saying now - Mike just pointed out that one of my posts ended up in the Battery Disconnect thread! Probably whilst I was amending the post and replying here - so ignore what I said on that front - my fault :roll:

So back on the issue - all I can say is that with a revision 'B' interface you may / may not have any luck - so may be worth a shot.
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by Itchigo55 »

Ah sorry *** !

VF7**************[VIN obfuscated, can be read by forum staff]
Last edited by GiveMeABreak on 22 Jun 2019, 10:58, edited 1 time in total.
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by GiveMeABreak »

Right,

C4 PICASSO / C4 SPACETOURER (B78) FAMILY SALOON 1.6 HDI 115 (DV6C) STT 6-SPEED PILOTED MANUAL GEARBOX

so the actual build date is 4th December 2013. This has the fully multiplexed electronic architecture.
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by Itchigo55 »

Right, so James couldn't read all the faults, however we did read U1F00 and B007A "passenger strap return pretensioner line fault" . There was a depressing amount of errors approx 35!
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by GiveMeABreak »

Unfortunately, not much help I'm afraid - did you clear the faults and re-run the test?

The first one is non-descript U1F00 just means the fault event is not stored in the faults log (useful I know).

As for the second one, there is some part of the fault code missing as there are 6 codes for B007A and each should have a further 2 characters after it:

B007A 11 Passenger’s strap return pretensioner line fault: Short circuit to earth:
(A part of the line is in short-circuit with the earth for more than 2 seconds)
Suspect: Passenger’s strap return pretensioner or Cabin harness or Connectors or Airbags and pretensioners control unit

B007A 12 Passenger’s strap return pretensioner line fault: Short circuit to positive:
(A part of the line is in short-circuit with a +12V supply for more than 2 seconds)
Suspect: Cabin harness or Connectors or Airbags and pretensioners control unit
B007A 13 Passenger’s strap return pretensioner line fault: Open circuit:
(No Data)

B007A 1A Passenger’s strap return pretensioner line fault: Resistance too low:
(Global impedance on the line is too small for more than 2 seconds);
Possibility 1: Resistance below 1,2 ohms : Short-circuit fault certain
Possibility 2: Resistance between 1.2 ohms and 1.7 ohms: Short Circuit fault or no fault detected
Suspect: Passenger’s strap return pretensioner or Cabin harness or Connectors or Airbags and pretensioners control unit

B007A 1B Passenger’s strap return pretensioner line fault: Resistance too high
(Global impedance of the line is excessive for more than 2 seconds);
Possibility 1: Resistance between 4.5 ohms and 10 ohms: Open Circuit fault or no fault detected
Possibility 2: Resistance greater than 10 Ohms: Open Circuit fault certain
Suspect: Passenger’s strap return pretensioner or Cabin harness or Connectors or Airbags and pretensioners control unit.

B007A 64 Passenger’s strap return pretensioner line fault: Present but not configured
(Detection of a "nominal" line resistance for more than 2.8 seconds even though the igniter is configured absent);
Possibility 1: Resistance between 1.2 ohms and 1.7 ohms: Short Circuit fault or no fault detected
Possibility 2: Resistance between 1.7 ohms and 4.5 ohms: Nominal impedance: No fault detected
Possibility 3: Resistance between 4.5 ohms and 10 ohms: Open Circuit fault or no fault detected
Suspect: Configuration of the airbags and pretensioners ECU or Airbags and pretensioners control unit.

So these are the possibilities, but without the rest of the code I can't tell you which is specifically relevant. I seriously doubt it is B007A 64 the last option as unlikely to be a misconfiguration of the ECU!

So I suspect this may be down to James' older interface.
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by Hell Razor5543 »

While there were a lot of errors about half said "ECU not recognised", but the others did not. Of these, I did NOT try to clear down error codes relating to Diesel additive (as it requested engine type), or the ones relating to the RH/LH reversing reels (there was an unlock request). I was able to clear down those that did not say "ECU not recognised" (I stayed well clear of any section which had this message (even if there were other errors in the section), as I did not want to brick anything), ran the diagnostic again (those errors had not returned), and then we went for a short run (about a mile) and tried again (these errors remained cleared). This was done through DiagBox, not Lexia.

We looked at all the error messages (even those in sections with an "ECU not recognised" message), and Matt took photos of each message (the summary part, as some had a LOT of details).

The airbag system threw up two errors, and one of these was "ECU not recognised", so I did not do anything here in the menus. However, Matt was looking underneath the driver seat (from behind) to see where the wiring was, and I pointed out it was at the front. The ignition was on, and when I touched the wiring bundle for the nearside front seat a warning message then popped up on the instrument display, relating to the airbag/pretensioner. Because of this I feel fairly confident we have a wiring issue; either a weak wire or a bad connection. I have suggested that (after following the correct disconnect procedure and then waiting for at least 10 minutes) it could be worth disconnecting the seat plugs, spraying in some PROPER contact cleaner, plug/unplug the connectors a few times (finally leaving them connected), reconnect the battery and see what messages come up.
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by GiveMeABreak »

Well good show for doing what you could - it does seem to point to a short or loose wire / pin, so hopefully the visit was not in vain.

You did the right thing, by leaving those other error codes as clearing them without being able to communicate with the ECUs directly may cause issues. The Lexia application won't work with this year model - it's far too late for anything past 2007 as it will no longer be updated to work with newer vehicles.

Well done both, just need to track down the swine wire.
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Re: Citroen Picasso B78 Lexia needed.. Airbag light

Post by Hell Razor5543 »

Now Matt has photos on his phone that show the various error codes (including the airbag error) it may be possible for him to convince the warranty company or seller to resolve it.

It was DiagBox that was doing the diagnostics, as (once I selected Picasso B78) it went straight into the Global Tests without giving me an option as to which package to use (which doesn't surprise me).