C6 electronic park brake.

[dowen]

I've just fitted front left frip and top ball joint, and in the process had to drill out abs sensor. The car has been on the Jack for a week, and as I expected the ABS light is on!
However the park brake is not engaging, when I apply it it briefly comes on and almost immediately goes off, (I can hear motor)
Can this situation be connected to ABS sensor? Or, is it just another C6Q (C6 quirk)

[wheeler]

Have you sorted the ABS sensor yet? If so you may need to go in & clear the fault codes out of the ABS & EPB systems. Alternatively driving the sometimes resets it.

[GiveMeABreak]

I've just fitted front left frip and top ball joint, and in the process had to drill out abs sensor. The car has been on the Jack for a week, and as I expected the ABS light is on!
However the park brake is not engaging, when I apply it it briefly comes on and almost immediately goes off, (I can hear motor)
Can this situation be connected to ABS sensor? Or, is it just another C6Q (C6 quirk)

The ESP ECU controls the parking brake ECU, so if there is a problem with the ESP / ABS system as you have stated, it will affect the parking brake too. It is by design and a safety feature. Hill Start Assist and Emergency Dynamic Braking all need the ESP system to be fully operational before these features will work, hence the warning lamp. Once you have replaced the ABS sensor and cleared the faults, it should return to normal, unless there is a further fault - in which case you should read the codes and pop them up here, where we might be able to advise further.

[dowen]

Thanks Mark, that's what I am hoping,I haven't driven it yet, maybe it will clear.

[Hell Razor5543]

Be aware it is possible that (until the car has been driven after the sensor has been replaced) the error will not clear. I had a failed sensor on a Xantia, but when I replaced it the ABS light remained on. I then started checking my work, but I could not find anything wrong. I had to then drive the car, and as soon as she hit 6MP/H (10KM/H) the ABS light went out and stayed out. This is because the ABS system was then receiving coherent data from all of the ABS sensors.

This is a safety function. Until the ABS system 'sees' coherent data from a 'failed' sensor (even if it has been replaced) it 'assumes' the sensor is still faulty (and just putting a resistor in the circuit (as a bodge) will not work), so it keeps the ABS function turned off.

[GiveMeABreak]

Not relevant on the C6 James - the ESP system has a self diagnostic that runs each time the vehicle is started - it the sensor is in place and working that will be all that is needed.

[dowen]

Hi Mark, OK sorted! But I'm puzzled! Left front sensor. Replaced with new, but rather than take air box off, I cut and spliced new sensor. This gave all warnings and diagbox said electrical fault! But as soon as I replaced with the complete
new sensor it immediately cleared! Handbrake ok too!

[GiveMeABreak]

So are you saying you 'un-spliced' it and replaced the complete sensor and its wiring?

These are very sensitive devices and any interference or a short will cause faulty signal transmission. Glad you have it sorted now though.