RangeRovers.net Forum banner

1 - 6 of 6 Posts

·
Registered
2006-2009 Range Rover MkIII / L322
Joined
·
5 Posts
Discussion Starter #1
Hi Guys,

My 06MY Vogue seems to be suffering from some brake issues. Over the last few weeks the brake pedal has become long in its travel and also somewhat spongy.

Pads and rotors are ok, and all the caliper side pins are working correctly, and nothing else in the brake system appears to have any visual issues either. I've bled the brake system using the procedure listed in the manual, including using a Blackbox Solutions Faultmate MSV2 to exercise the ABS Modulator, however no air was found in the system nor has the pedal feel or travel been improved.

However when bleeding the system with the faultmate, I experienced an interesting problem when I got to the Front Right wheel (last in sequence). Once the bleed nipple was opened and the pedal was pumped, the car kicked in its ABS function and effectively started to modulate the fluid flow to that wheel, to the point where it was not possible to even pump the pedal as it had gone rock hard. This was accompanied by the sound of the modulator motor running and the clunking of the ABS valves. You could also visually see the fluid in the tube attached to the nipple being pulled back into the car (as if it was being sucked back)

Even driving the car before this brake bleed, you could hit the brakes hard a few times in succession and this would cause the pedal travel to increase more than normal. In addition it is also experiencing issues with the DSC as described in the attached Technical Service Bulletin (DSC cutting in on corners when you would not expect it too).

Based on these issues my diagnosis is leaning toward the ABS Modulator being at fault, however the car is not displaying any ABS/ETC faultcodes, which considering the list detailed within the workshop manual that the ABS module is capable of displaying just seems a little unusual.

Analysing the components within the entire system the only other item that seems like it could be at fault is the master cylinder. Its failure could be justified as the reason for the lack of fault codes too. And if you pump the pedal and remove the vacuum assistance you can feel the pedal falling away under your feet a little.

In all of this the car still feels like it has braking power, however the pedal travels a large amount and doesn't inspire much confidence in the process.

Am curious what other peoples thoughts might be in regards to this, or if anyone has had a similar experience. I am not a person that ever gives their car to anyone to work on, and coupling this with my dislike for bleeding brakes is kind of leaning me to just replacing both ABS modulator and master Cylinder, however $$ wise I would like to avoid doing both.

Regards,
Daniel.
 

Attachments

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
228 Posts
This does sound strange. The first thing I would do it completely exchange the brake fluid. This procedure is easy with a correct brake flush kit for around 20GBP (not sure what the Aussie forex rate is). This kit comprises of a pressure vessel which you connect to a spare tyre and it attaches to the brake fluid reservoir. Fill it with new fluid, connect to the tyre and then open the bleed valve on the caliper (all a one man job). There is no need to pump the pedal! Do this on all four corners.

What I find strange is that the ABS unit kicked in when you were bleeding, and this could have pulled air into the line(s). You describe what you did well, however the symptoms you describe are classic air contamination of the brake lines. By exchanging the fluid completely should eliminate all traces of air and old fluid from the system. The ABS should only kick in when engine is running and when the system detects that one (or more) wheels have zero revolutions when others have a rotation. As your car was static - seems you could have an ABS control or modulator problem, and also master cylinder problem like you say.

Start with the simple brake flush and take it from there. Ideally you should also get LR to read the fault codes - not a faultmate or the like as they cannot always communicate with all systems correctly.
 

·
Registered
Joined
·
256 Posts
Interesting so the Spare tire is being used to push the fluid like it would if it were being hooked up to a BG machine ?
 

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
1,932 Posts
do you know if the brake fluid has been changed from the the factory fluid to some other brand?

If the fluid have been changed then there is a good chance that the seals have gone bad in the MC.
I suggest to only use the factory fluid so to keep things working .
From the info provided i would install a new MC and fill the system with factory fluid,
the reason the ABS started working may be that one of the brake circuits isnt getting the same pressure as the other side.
 

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
228 Posts
Yes, the tyre is used as a pump.. it is quite good, and very easy to use. Just fill up the reservoir with fresh fluid, connect to the top of the cars reservoir, connect to the spare tyre, then at your leisure open up the bleed valve on the caliper and watch the fluid get pushed out. Very very easy - and no mess or helper. Just dont forget to top up the spare tyre when you have finished.
 

·
Registered
2006-2009 Range Rover MkIII / L322
Joined
·
5 Posts
Discussion Starter #6
Hi Guys,

Thanks for all your comments.

I pushed a large quantity of brake fluid through the system whilst bleeding it, so I am confident that the fluid itself is eliminated as the problem.

Am starting to think that I might just replace both, as I know the Modulator needs to be replaced as per the Technical Service Bulletin.

Also speaking with Blackbox Solutions, the Faultmate is able to read every faultcode on the car as per what Land Rover can. Even if the unit is unable to interpret the data for some reason, it will still display a reference number that can be used by them to investigate further.

Regards,
Daniel.
 
1 - 6 of 6 Posts
Top