C5 brake fluid change

GB · Unread post by GB » 12 Feb 2010, 13:37

Apart from a brake bleeding kit are there any other "unusual" tools required for C5 brake fluid change?

Someone on this forum mentioned that Lexia is required for a proper C5 brake fluid change - is this the case?

Cheers,
GB

Clogzz · Unread post by **Clogzz** » 12 Feb 2010, 13:56

Not for brake fluid change, as it’s an ordinary system with undyed DOT 4 fluid.
The suspension LDS fluid change is supposed to be done with a Lexia to open an electro valve, but even that only releases very little more fluid.

Unread post by **myglaren** » 12 Feb 2010, 16:00

I'm reasonably certain that a Lexia is supposed to be used to open a valve in the ABS when pushing the pistons back into the calipers, otherwise damage can be done to the ABS.
Not required for a straight brake bleed AFAIK.

uncle buck · Unread post by **uncle buck** » 12 Feb 2010, 23:38

myglaren wrote:I'm reasonably certain that a Lexia is supposed to be used to open a valve in the ABS when pushing the pistons back into the calipers, otherwise damage can be done to the ABS.
Not required for a straight brake bleed AFAIK.

When pushing the pistons back on any car it's good idea to clamp the flexi hose & opening the bleed nipple so you don't push the fluid back through the system

Cheers.

Citroenmad · Unread post by **Citroenmad** » 12 Feb 2010, 23:48

So in order to change brake pads you need a lexia? Surely not?

Ive done the back brakes on the SX C5 without any problems.

Unread post by **Paul-R** » 13 Feb 2010, 08:48

Citroenmad wrote:So in order to change brake pads you need a lexia? Surely not?

Ive done the back brakes on the SX C5 without any problems.

As have I on my C5.

As I understand it if the ABS gets confused through unequal amounts of brake fluid passing throuhj then you need a Lexia to reset it. So, if you're careful, you don't need a Lexia.

wheeler · Unread post by **wheeler** » 13 Feb 2010, 16:58

You deffo dont need a Lexia to change C5 brake pads. You do need the Lexia however to purge the ABS unit if it has been removed or a new unit fitted.

Citroenmad · Unread post by **Citroenmad** » 14 Feb 2010, 20:58

Thats good to know, i didnt think it would have been somehting needed to change brake pads, but you never know on modern cars!

I had my LDS fluid changed recently, i know lexia is needed for that, bleeding the suspension system.

wheeler · Unread post by **wheeler** » 14 Feb 2010, 22:24

Citroenmad wrote: I had my LDS fluid changed recently, i know lexia is needed for that, bleeding the suspension system.

You don't need a lexia for that either & you dont need the Lexia to de-pressureise the system.

Citroenmad · Unread post by **Citroenmad** » 14 Feb 2010, 22:30

According to my local citroen indy, lexia is needs to depressurise the system. As when low is selected in a C5 it doesnt go into fully low. Though i can only go on what ive been told.

cachaciero · Unread post by **cachaciero** » 14 Feb 2010, 22:38

Citroenmad wrote:According to my local citroen indy, lexia is needs to depressurise the system. As when low is selected in a C5 it doesnt go into fully low. Though i can only go on what ive been told.

That's true, with a Lexia you can overide the system and open the the valves to allow the system to depressurise fully. However without a Lexia you can still de-pressurise the system mechanically, there are a couple of bleed valves for this purpose.

cachaciero