Brake Fluid low

[giw12]

Hi

About 3 weeks ago the low brake fluid light flashed up very briefly when I turned very sharply. Since then the message has been displayed for a longer and longer period and as of yesterday, on the drive to drop off for a service, the message was almost permanently displayed. The fluid level in the resevoir is low so it’s not going to be the level sensor.

The indie has had a good look but can’t find anything, and even the 4 year old/40000m front brake discs look fine (rears changed 2 years ago).

Any ideas why fluid levels are dropping so quickly? There is no record of a fluid change in the last 6 years so maybe this is the issue?

Car is 2006 D5 163hp auto.

Thank you

[SwissXC90]

It's a sealed system.

You can only loose brake fluid through a leak.

Look carefully everywhere.

[robsterpaterson]

You say that the front discs look fine, what about the pads? What about the rear pads?? As the pads wear, the fluid level will drop as the pistons sit further out of the caliper body.
If they're OK, as Swiss says, the fluid has to be leaking somewhere. Maybe try topping the fluid up and either have someone pump the brakes while you check ALL of the lines, hoses, unions and calipers or fashion a length of wood to hold the brakes under pressure. Be better to have a glamorous assistant on hand to pump them as should be easier to spot a leak that way vs constant pressure I reckon.

[harveys]

The Brake master cylinder could be leaking have a good look above the pedal in the car.
or could be leaking into the servo not so easy to find.

[nu11eaf]

As previously mentioned, its most likely due to brake pads wearing down, this is quite normal, as they wear the brake fluid level drops, just add a little to bring it above minimum level, but not too much as when you eventually replace the pads and push the pistons back to get new pads in, the fluid level will rise and overflow if you put too much in and don't take some out before pushing pistons back. (Warning brake fluid will damage paintwork so take care)

"BUT" Check that there is not anything leaking to be sure, as warning lamps should never be ignored and the cause found, leaks in the brake system usually result in air getting in and a spongy brake pedal.

[gmonag]

About 3 weeks ago the low brake fluid light flashed up very briefly when I turned very sharply. Since then the message has been displayed for a longer and longer period and as of yesterday, on the drive to drop off for a service, the message was almost permanently displayed.

So you drove for 3 weeks with no brake fluid.........!?

Those warnings are there for a reason.

[giw12]

Originally Posted by gmonag

So you drove for 3 weeks with no brake fluid.........!?

Those warnings are there for a reason.

Not sure where I said there was no brake fluid....I monitored the level in the reservoir.

Yes, I'm aware of the purpose of warning lights/messages.

[giw12]

Apparently the pads are all fine as well.

After 4yrs/40k, can I really drive so like Miss Daisy that my front pads are still fine?

[SwissXC90]

Originally Posted by giw12

After 4yrs/40k, can I really drive so like Miss Daisy that my front pads are still fine?

Totally

Brake pad wear is governed primarily by two factors:

• Geography (hills cause you to brake more)
• Driving style (some drivers brake harder and more often than others)

[XJSDriver]

I agree with Harveys - as yours is a 2006 after 12+ years could well be the seals in the master cylinder are past their best allowing fluid into the servo. Not sure how you test for this though; I guess if everything else is checked and leak tight, then has to be the master cylinder.