C5 brakes problem help needed urgent

skinhead · Unread post by **skinhead** » 03 Sep 2010, 20:44

just had my front pads & disces replaced but pedal feels soft/spongy & pedal sinks to floor if heavy pressure held on it
Garage says (after re bleeding & no air in system)) that its due to new pads need to bed in
seem to remember some one else had simler problem.can any one advise please
supposed to be going away with caravan tommorow

Unread post by **myglaren** » 03 Sep 2010, 20:51

Never had that symptom on mine after pads/discs were replaced.

Give it a bit of a run with some heavy braking and see if that cures it, otherwise I'd be very wary of dragging a van around.

cachaciero · Unread post by **cachaciero** » 03 Sep 2010, 20:58

I don't really follow why the brakes would need bleeding after changing the pads.

However to bleed the brakes properly on a C5 a Lexia is required to open a couple of valves in the ABS bit of the system.

cachaciero

skinhead · Unread post by **skinhead** » 03 Sep 2010, 21:00

I'v just took it out for a run & tried some realy heavy braking,it stops fine & the anti lock system cuts in,but if the foot pressure is held on the pedal it gradually goes to the floor.I know its not right but the garage insist they will firm up.Im at a loss as what to do now apart from take to another garage

Unread post by **myglaren** » 03 Sep 2010, 21:28

If the pedal is sinking to the floor when stationary there is definitely a fault.
My guess would be seals weeping somewhere, Master cylinder would be the first suspect unless you can see any fluid leaking from the calipers.

As cachaciero has said, a diagnostic computer is really needed to open some internal valves. The quick and dirty way is to open the bleed nipples while winding/pushing back the pistons and allowing excess brake fluid to escape there, otherwise it is forced back into the ABS system with potentially serious results.

Are they Citroen qualified at all?

skinhead · Unread post by **skinhead** » 03 Sep 2010, 21:29

cachaciero wrote:I don't really follow why the brakes would need bleeding after changing the pads.

However to bleed the brakes properly on a C5 a Lexia is required to open a couple of valves in the ABS bit of the system.

cachaciero

at the risk of seeming an idiot.whats a Lexia ???

Unread post by **myglaren** » 03 Sep 2010, 21:30

skinhead wrote:
cachaciero wrote:I don't really follow why the brakes would need bleeding after changing the pads.

However to bleed the brakes properly on a C5 a Lexia is required to open a couple of valves in the ABS bit of the system.

cachaciero
at the risk of seeming an idiot.whats a Lexia ???

Citroen dedicated diagnostic computer.

wright · Unread post by **wright** » 03 Sep 2010, 22:48

i noticed mine was like that a while ago, bleeding the back helped and i have a better pedal since replacing disks and pads but i havn't noticed the pedal going down since, it hasn't been a problem they work fine, although under heavy braking before the new disks and pads the pedal did go down a bit but the car stopped fine, but the disks were well past their best pads were only a few months old, pads were ftted just before i bought it.
i'll try mine tomorrow and see if its the same

citronut · Unread post by **citronut** » 04 Sep 2010, 11:14

this sounds like exactly the same fault i have with a F*A*T SCUD O (PSA under the skin) but non ABS,

also seems to have startted after fitting front pads,

i fitted a new master cylinder and the fault is still there after presure bleeding twice,

regards malcolm

mooseshaver · Unread post by **mooseshaver** » 04 Sep 2010, 15:56

Have you noticed any liquid sort of stains on the wheels?
When I had my brakes done I was told they felt spongy because the pads needed bedded in. Same symptoms as you.
I knew something was wrong, and I saw the liquid stains on one wheel. They started in the middle and spread out with driving.
Can you check the brake fluid level then press the brakes lots then check level again?
I took mine back with these evidence and was told the mechanic had maybe got dirt in the system when they changed the pads.