So I have lost pressure on the brake system. Luckily I have the Range Rover to drive for the time being but I would like to get the Jag back up for non snow days for the gas mileage lol. Ok I'm pretty happy with the way the Rangie has been coming along so here's a picture



The brake fluid resivoir is topped off and showing no signs of leakage. The mineral oil is topped off. Pads are good and the calipers are not frozen. I get a every so often low brake pressure, but no abs failure messages.

I noticed a few days ago I'm getting mineral oil leakage on the brake pedal inside the cabin. I couldn't tell if the abs pump was running. The fuse isn't blown but I know that doesn't mean a relay didn't fail.

My question is does the abs pump have anything to do with brake pressure? If it doesn't were do I need to be concentrating on to get the brakes back up and running. This system is a bit more confusing than what I'm used to. Thanks in advance for any ideas or guidance.

Oh and Merry Christmas lol

 

Hi Army, I can only go off my 92, and I'm no expert, but;

When you switch the ignition to 3, you can hear the brake pump come on behind the dash, sounds like a fading ZZZZzzzzz.

If you then listen carefully with the engine running, when you gently press the pedal do you hear the same noise. Apparently this would indicate a bad accumulator sphere not holding pressure, and causing the pump to work overtime.

You may also see the red pad warning light flash together with PAD on the VCM even if your pads and sensors are new.

This file might help you get a better oversight about the system and help with your diagnostics.

S73 hydraulics publication XJ40 pdf (supplied by motorcarman)

Although visible oil would tend to push towards a bad seal somewhere.

(Rangy is looking good)

 

Thanks that diagram is perfect. I got an answer in another thread oddly enough and it looks like I'm going to do a homemade vacuum booster conversion on it. I have a fabricator buddy making me the adapter plate as we speak.

Oh and thanks on the Rangie

 

Well work was slow since I dedicated the bulk of my time to the Rangie. I've been driving it every day and lovin life. I got most of the work on the vacuum booster conversion done today and will be finishing it up tomorrow. Grand total of the cost will be $115.00 no stupid kit needed. Once I confirm everything is working I will post up a how to for the budget minded.

of course Range Rover love pics



My RRC sitting next to a stock Discovery G4 edition it looks so short compared to mine...