Interesting little problem on my 2004 XJ8, 157,700 miles. When I am in the process of braking after about 3 seconds the Low Brake Oil Level warning and the Handbrake (parking brake) lights both come on. They stay on for about 3 seconds once I have come to a complete stop and still have my foot on the brake. Then the Low Brake Fluid light goes off first, followed by the Handbrake light 1-2 seconds afterwards. Nothing feels wrong and the car brakes as it always has - no difference in feel, stopping distance, etc.

I can also generate the same issue occasionally when I really accelerate hard from a relatively slow speed. Obviously I am not touching the brake pedal at this point!

Any idea where I should start looking? No codes are generated that I can see. All the pads are relatively new, the brake fluid level looks fine in the reservoir. I am not sure when the brake fluid was last changed - possibly 2012 around 66,000 miles.

 

Hi,

I had low brake fluid low and parkbrake fault warnings recently on my XJ8. I would get them randomly along with DCS not available warnings and ABS warnings. I could sometimes trigger the faults when braking from speed and they would disappear once I came to a stop. I got the faults a couple of times on hard acceleration. I could sometimes trigger the faults when manually using the windscreen wipers as well.

My problem was being caused by a heavily corroded ground point at the front of the car behind the headlights.

I think my ground point was actually moving slightly under road conditions and whilst the car was in motion caused by movement.

I cleaned two of the three points and one of them snapped clean off when I tried to unbolt it. I had to relocate the snapped ground point which has fixed my electrical issues.

You problem may not be this but it does sound suspiciously like a ground or electrical issue. If your brake fluid level is actually ok then I'd check those ground points as they cause all sorts of electrical issues if they are corroded or in a poor state.

Thanks,

Chris

 

Chris,

Many thanks - I cleaned the earth points and there was some white powder on the threads but not much. I also found a few ground connections in the trunk and cleaned those up too. Unfortunately the problem still exists. It is very predictable as to when these lights will come on which is the mystery to me! Not every time I hit the brakes but when I have my foot on the brake for several seconds, such as when slowing down for a junction. After 2-3 seconds the lights pop on and then stay on for about 3-4 seconds when I am at a complete stop or I take my foot off the brake. The low brake fluid light will go off first and about 1-2 seconds later the handbrake light goes off.

 

Ok. It was worth checking. My warnings were very random but sometimes the warnings I could trigger by braking and accelerating hard. Someone else on here hopefully will have some idea of what the problem is. I presume there is a sensor in the brake fluid reservoir so possibly this is having a fault. I hope you manage to find the cause.