DS5 D'Sport ECU issues

[Alan R Taylor]

Hello everyone i am new here so hello to all.
I have a 2013 DS5 D'Sport with the semi automatic gearbox and all the toys. I was driving along happily at about 55mph when all of a sudden my dash lit up like in as a disco. Warning of Engine Failure. Then Gearbox Failure. The Handbrake Failure. Then ESP Failure. Then Role Back Failure and more.
So it went into limp mode and i nursed it to the side of the road and awaited the AA.
The AA said after running a diagnostic that the gearbox module did not seem to be speaking with the ECU so towed it home.
Thinking that it may be gearbox i booked it into a gearbox specialist.
After nursing it to them they ran an in-depth diagnostic which resulted in a loo role length of fault codes so they scratched their head as nothing was saying gearbox issue bar that Gearbox Fault warning. So they cleared all the codes and tried it and in under 30 seconds warning bells rang with all the same warnings as before and straight into limp mode.
So they scratched their head which is not like them as they know their onions.
They then spoke with a friend who runs a place that specialise in all things ECU who it is now booked into for them to go into the cars brain and see if they can shed some light on what might be the issue.

The car itself is wonderful and has 97 thousand on the clock but the engine runs like a swiss watch until this, she has all her services up to date and is treated like a family member.

So i was wondering if any of you good Citroen owners had ever experienced anything similar or may have any ideas on what sort of thing may cause such a varying array of warnings which included door lights, stereo, steering wheel and all sorts of oddments.
But both times it said intermittent ECU fault but no clue as to what that was.

Many thanks Alan.

[Hell Razor5543]

Hi, and to the Forum.

My guess (and this IS a guess) is that the engine bay fuse box is at fault. I have seen (on the forum) threads where there have suddenly been numerous faults, and the most common cause was the engine bay fuse box. This is where almost everything gets its' power, and there are also communications happening here. If you have the codes it could be worth posting some of them up here.

[GiveMeABreak]

We'd really need the fault codes as you have to remember that the Gearbox ECU is linked to the ESP and BSI as well as the engine ECU, so the data form these systems rely on everything working properly. A fault in one system like the ESP will trigger related faults in the Electronic handbrake for example.

Anything like this is really a dealer job as it is not just the piloted gearbox expertise that is needed it is the knowledge of the rest of the vehicle and how the systems interdepend on each other. It could well be the engine fusebox, as these can suffer with a dry solder joint or from water ingress, especially if it has been driven through floods in the past.

When I see all the numpties driving their vehicles through places like Rufford Ford, I often wonder who the poor soul is that ends up with any of those when they sell it on. The quickest way to stuff the electronics.

If you have the fault codes then do pop them up along with your VIN (automasked on post submission) and I'll take a look.

[RichardW]

It's likely the engine has thrown some error code, which in turn upsets the engine speed signal on the CAN bus, which causes the gearbox and ABS / ESP / handbrake module to throw its toys out the pram. What engine is in this? What were you doing when the light come on - accelerating or cruising? Often EGR valve faults are at the root of these, but you really need to see the fault codes to try and get a grip on what is going on.