ABS Warning

Hello, hoping somebody may be able to shed a little bit more light on the following issue. 1st Citroen in the household
My son inherited his grandads C3 8 months ago and since then it has been stored outside with no use, everything running ok before and was a daily runner, 83K miles.
He now has a provisional driving license and wants to start learning in it, but MOT has expired.
Last weekend we had a look over it, cleaned it, checked fluids etc. and purchased a new battery (existing one was dead, not surprised as it had never been put on slow charge ).
Car started 1st time and slowly moved the car forward/backwards, all good, brakes working, no strange noises.
Booked in for its MOT and pulled out of the drive, drove about 20 metres and ABS warning came on, brakes seem to be working ok.
Looking at several ABS posts on this forum, thought it may be worth starting on the speed sensors, remove and clean etc. I do have a ELM327 OBD reader but since putting the car in the garage no ABS warning has come back on, presume it gets reset after a power cycle?
Any pointers of what else to check?
Thanks in advance.

Hi

ABS warning will clear itself, automatically when the fault is cleared and it gets a good signal from the wheel sensors, usually very quickly.

Cleaning the ABS magnetic track usually does the trick and the fault clears itself soon after on the next drive.


Bad batteries can also play havoc with the ABS warning and airbag lights.

It was probably the battery...

C3CAR wrote: ↑Wed Apr 19, 2023 1:03 pm Hi

ABS warning will clear itself, automatically when the fault is cleared and it gets a good signal from the wheel sensors, usually very quickly.

Cleaning the ABS magnetic track usually does the trick and the fault clears itself soon after on the next drive.


Bad batteries can also play havoc with the ABS warning and airbag lights.

It was probably the battery...

Thanks for the quick response and information. I will have a go at cleaning the ABS magnetic track this weekend. Good call on the battery too, i know that can give odd error codes on other makes.

Having spent the morning removing the rear hubs and cleaning the magnetic ring, they were both covered in dirt/rust particles? refitted both hubs, wheel sensors and started the car.
ABS light now comes on within a few seconds of the car starting, every time the car is started. So different to what I was experiencing originally.
Am I now looking at the ABS pump being the fault? how can you check, should it cycle when the car starts?
Thanks

Deano3737 wrote: ↑Sat Apr 22, 2023 10:21 am Having spent the morning removing the rear hubs and cleaning the magnetic ring, they were both covered in dirt/rust particles? refitted both hubs, wheel sensors and started the car.
ABS light now comes on within a few seconds of the car starting, every time the car is started. So different to what I was experiencing originally.
Am I now looking at the ABS pump being the fault? how can you check, should it cycle when the car starts?
Thanks

You can check which wheel sensor is bring up the fault by connecting lexia tool. This will pinpoint which wheel.

You can also look at lexia to diagnose the ABS pump faults, several diffeewnt fault codes will being up the same ABS light.

I wouldn't jump into the ABS pump just yet, be sure it's not a wheel sensor and you are checking the correct wheel sensor for the fault.




Typical Citroen C3 Lexia ABS checks

Thanks. I will source a Lexia tool and go from there.