DS3 electrical issues

[aledsav1]

Hi All, hoping someone can shed some light

DS3 E-HDI DSTYLE 2011

over the last 2 months been getting ESP/ASR fault come up and car shuts engine down and have to stick clutch in and coast over to side of road, turn off restart and then drives again, this happens random times sometimes never, most of my driving is hour-2 hour runs, can happen within minutes of setting off to not happening to happening after an hour of driving. And very occasionally car has struggled starting first time, but that has happened maybe 4 times usually from cold.

Garage found corrosion on the battery terminal, cleaned etc then the stop start started working (had car 6 months and it never worked, I wasnt sure it had stop/start) but the esp/asr issue persisted

Once or twice instead of esp ecomode error has occurred with the same results.

I switch ecomode off everytime I drive and didn't experience the issues for weeks, until the other day it happened 2 times in succession during one run with eco off.

Garage has had this in several times re this and have checked all grounds all wiring, abs sensors etc, battery and alternator all good, says it throws ups loads of faults but say the only one that continues to come up after being cleared is BSI/BCM error:

F52A Fault in Built-in Systems interface (BSI): Outputs inhibited definitively (Refer to live status of the power outputs)

suggest I replace the BSI unit, though are not 100% its that..

Yesterday I took the BSI out opened it up (its a 2016 model so not original to the car) and have to say it looks prestine, now I know that does not indicate there is not a small component blown or something else not visible going on, but I was expecting to see something maybe a bit of corrosion on some small component/s, also had a look at fuse box/battery/ecu and cannot see any obvious issue

Does anyone have any ideas or should I just buy another BSI, send them both off for programming etc..could do without the lack of a car for that period

Many thanks

[PaulC5]

Some times ESP/ASR apparent faults can be due to a low battery voltage but I guess the battery has been checked. If it is old though you could consider replacing it. However, I suspect that would not cause the engine to shut down. Possibly there is a poor wiring connection. When it shuts down does the engine management light come on ? If so a fault code would be stored as well as freeze frame data that might give a clue as to the fault ?

[aledsav1]

No engine management light just the esp/asr error comes up, before I go ahead with the BSI replacement I'll check behind the door panels and any other areas I can get to to check the wiring

[PaulC5]

Is the garage you are using a Citroen/DS/Peugeot dealer ? If not you could try a dealer since they could have better diagnostic equipment to diagnose the fault.

Beware if you fit a bsi from another car your car will then adopt the higher mileage of your existing bsi or that of the replacement. You may also need to replace your keys and you will need a diagnostic to code the radio to the replacement bsi. I do not know if these things can be done by sending off the bsi somewhere or if it has to be done on the car.

[aledsav1]

I have bought a used BSI, and will be sending them both off to be cloned its realitively simple, if i had the equipment I would do it myself. As for the garage just one of my locals, I might look into the dealers, but given the current none dealer garage prices the car wont be worth it:)