Auto Handbrake fault

[RichardW]

Bears an uncanny resemblance to the one I posted...

Alan, in your pics the code is coming up in the handbrake. Are there any codes in the ABS ECU? If not, I'd be leaning towards there being a fault in the handbrake unit.

[Aland97]

This was the rest of the report I done yesterday… no other codes in any areas apart from a couple of bulbs which I’ve now replaced and something with the stereo..

@richard and givemeabreak I really appreciate the help so far it means a lot 🥹

[Aland97]

Going down the whole power and voltage route…. Live data said supply voltage to the handbrake ecu was 14.4v and obviously it’s not working… where next after the motor can I check with a multimeter to see if powers coming from it and how much? That would make sense right??

[RichardW]

I would check the voltage at pin 5 on connector to the handbrake unit. Check with a meter, then ideally put a load, e.g. a headlamp bulb between it and the ground on pin 1 to check that it can support a load. I would want to get it on Diagbox before condemning the unit though...

[Aland97]

Ok I’ll give anything a try at this stage… but further down the line, any idea where else I can test? Maybe nearer the wheels?

[Aland97]

Just another quick Q…. If I release it manually what will happen?? Obviously I’ll be able to move it but will it lock up again once I try an apply the handbrake and if so can you then manually release it again?? Or is it a one time use thing??

[GiveMeABreak]

Yes, when the ignition is switched on again the parking brake reinitialises - so be aware not to switch the ignition on if working on the rear calipers!

From the manual:

In the event of the electronic parking brake malfunctioning or the battery running flat, an emergency manual device can unlock the parking brake.

Immobilise the vehicle, with the engine running, by engaging first gear (manual gearbox), position P (automatic gearbox) or M or R (6-speed electronic gearbox), then switch off the engine.

If it is impossible to immobilise the vehicle, do not action the control and urgently contact a CITROËN dealer.

• Fetch the vehicle blocks and the unlocking device (braided cable) from the toolbox.
• Immobilise the vehicle by placing blocks at the front and at the rear of one of the rear wheels.
• Slide the front left-hand seat back as far as possible.
• Lift up the floor plug B in the carpet under the seat.
• Pierce the tab C on the tube D with the unlocking device.
• Place the unlocking device in the tube D.
• Turn the unlocking device clockwise. For safety reasons, it is essential to continue turning the device as far as it will go or until you hear a knocking noise. The parking brake is released.

Remove the unlocking device and store it with the blocks in the toolbox.

The operation of the parking brake reinitialises when the ignition is switched off then on again. If the reinitialisation of the parking brake proves impossible, contact a CITROËN dealer.

The subsequent time required for application may be longer than during normal operation.

[Aland97]

Evening all, not done much the last couple of days to it but decided to use the manual release tool to see if it released easy to which it did… managed to turn it round off the drive etc just fine, the P light on the switch turned off but the (P) on the dash remained flashing… turned off the car locked it and got back in it and the handbrake didn’t reset… not sure if it was supposed to or not tho so now it’s in gear on a flat drive…

Should it have reset once ignition was off and back on??

[GiveMeABreak]

Yes Alan under normal conditions, but as you have a fault it is not applying, so to be expected and Citroen recommend chocks until you get it seen to.

[Aland97]

Yeah I’ve got chocks under both back wheels, I am very tempted to just try a refurbished handbrake motor as part of process of elimination etc… can’t hurt matters or make them worse I guess lol

[Aland97]

Good evening all, me again lol

I’m looking at buying a replacement handbrake motor as I’m adamant that’s the fault (call it a hunch) but my Q is… does the part with pipe that the release tool goes down come off of my existing one as all the ones I’ve seen on eBay etc don’t seem to show it?? So it’s confused me.. and also, is it straight forward to remove the cable from the existing one and refit it to the replacement one? Thank you, and once again any advice will be greatly received…

[Aland97]

Evening all…. Been a few days so thought I’d update… before digging through all the wiring diagrams and other components I thought I’d change the actual handbrake motor/ecu and see what happens….

The pic was the result