Citroen C1 all four brakes seized

[Gad-Westy]

This is a friend of a friend's (damsel in distress) Citroen C1 with an unusual problem. It was parked up yesterday and when the owner returned, all four wheels were seized. My cousin went to help out and bled a tiny bit of fluid from each nipple so that the car could be moved somewhere sensible.

Have been chatting to my cousin about it this morning and we've assumed it's likely to be a fault with the master cylinder not returning. This tallies with what he found because, after bleeding, he reapplied brake pressure and the brakes seized again. Before any work commences, is there any other area that is worth investigating?

[Qwert1e]

I'm not sure a master cylinder is capable of failing in that way. I'd be suspicious of what's going on in the ABS system. It's a new one on me though.

[kev b]

I have seen this happen on motorbikes when the reservoir is overfilled, the fluid warms up and expands holding the brake on.

I would think it far more likely that the master cylinder is faulty, might be worth checking the pedal assembly for binding as well.

[Old Merc]

kev b said:

might be worth checking the pedal assembly for binding as well.

I agree its got to be something like that??

This is a very odd fault for a modern car with duel circuit/ABS etc.Old cars it would defo` be the m/cyl.

Now then,don't these C1`s have the Master Cylinder/Servo on the near side?? with a bar and linkage connecting across to the pedals?? if there is no free play in the pedal,its like driving around with the brakes on.

[Gad-Westy]

Sorry for the dealy chaps, didn't realise there had been replies. Cheers all.

This saga gets stranger. Apparently days earlier, the car failed its mot for no brake lights. Not sure why it was still being driven but that's another question. It's been taken to a garage to be repaired. They claim they have fixed fault by diagnosing that the brake light failure was caused by the LED centre light being wired incorrectly (+ and - swapped) and that fixing that has rectified brake locking issue. I'm racking my brains here as to how that is possible but prepared to be enlightened.