Active brake assist fault

[dylan26__]

Hiya, my friends Ds ds3 has previously been in an accident where the car had activated the emergency braking procedure automatically. Even though the car has been fully repaired it still has this fault. It indicates to take it to Citroen / Ds dealership but they want £125 for diagnostic and then further for the "repair".

I know in reality they just need to set a parameter in the ECU somewhere but still, if there's anything I can do to reset it at home please let me know.

The code I have is: 041A
Vin: VF7**************[VIN obfuscated, can be read by forum staff]

[GiveMeABreak]

I suspect you won't be able to do anything unfortunately.

The only parameters I'm aware of are to do with the Airbag Control Module that deactivates and records an accident that requires replacement for safety reasons.

If you are referring to the Active Safety Brake that uses the camera and the ESP system, then I'm not aware of anything to be reset here.

The diagnostic is a standard charge for up to an hour of diagnostics time, which may resolve the issue, but in some cases if there is follow on work, they don't charge you the diagnostic time, just the repair - it depends on the dealership, but you'll have to bite the bullet I suspect as you'll not be able to do anything yourself and this may be an issue with an MOT under section 1.7 if there is a warning lamp on for Emergency Braking Systems - as if the warning is on it's a Major Fail.

[dylan26__]

Yeah the active city brake, no light illuminates on the dashboard as you can actually disable the city brake in the multimedia screen.

The car has a laser sensor integrated within the rear view mirror sensor cluster
Does any description come up with that fault code / vin?

The only description I get through my thinkdiag when I scan the car is

"Code: 041A

Automatic Braking On Risk Of Collision (In Town)

Function Fault: Detection Of An Impact

Not Characterised"

I have many abilities with the thinkdiag obd including completely disabling the cars knowledge that city brake exists on the vehicle but that's not much use to us. The fault falls under the bsi module and I'm able to clear it as it's not a permanent fault but it just comes straight back.

Anyways, thank you as always speak to you soon

[dylan26__]

(For clarification the braking system works completely as normal this is only for emergency city braking)

[GiveMeABreak]

Yes, I see you have the other system with 2 receivers and 1 laser emitter, so this being a different system, after an impact or collision, it's a dealer level job, as they may have to go into the BSI and restore functionality after an impact. You can't do this offline, as the BSI is in secure mode for models of this build date I suspect, so needs dealer-level access and log-in to the servers or paid access with official software.

[PaulC5]

If the accident repair was done under an insurance claim, surely the fault should have been repaired as part of the claim. Has the car been taken back to the repairer to be sorted ? If the repairer did not have access to Citroen diagnostics then they should have taken it to somewhere that does, this happened when we had a C4 accident repair that needed a new abs pump and that needed coding to the car.

[GiveMeABreak]

Repairers may well not be aware of ALL the technical / safety requirements Paul, especially with later ADAS systems - and there are multiple types of systems fitted. My later vehicle uses the camera and sensor input for collision detection and active safety braking, so has no radar module, so has nothing to reset afterwards I suspect, unlike this one that specifically needs the system reactivating.

[dylan26__]

Yes, I see you have the other system with 2 receivers and 1 laser emitter, so this being a different system, after an impact or collision, it's a dealer level job, as they may have to go into the BSI and restore functionality after an impact. You can't do this offline, as the BSI is in secure mode for models of this build date I suspect, so needs dealer-level access and log-in to the servers or paid access with official software.

Ah alright, thank you. Will just bite the bullet and call them. Worth a try!