Brake warning Light on 1999 t2 TDI

[Midlander]

Hi All, looks like I need your help again

Today whilst driving I had the Brake warning light come on. after a while it went off, but after braking to a junction, came on again.
I got home, looked at the manual.
Says either Vacuum or Fluid.

Checked the fluid no loss.
Not sure how to check vacuum pipes for leaks.

There's A Black cylindrical relay that makes a loud clunk behind the trim on drivers side footwell, that when it does so, the warning light flickers.
Also, is this connected to the Vacuum warning sensor ? (on inner wing, passenger side, below the fuel filter) just wondering as the VWS looks a bit corroded round the connector. also the rubber pipe that goes to it wasn't on very far. (pushing it on further hasn't cured the problem)

I've located various pipes coming from the brake servo, round the back of the engine and down the passenger side of engine bay.
It tees off to the Vacuum sensor with the main pipe carrying on which looks like under the engine and back to the drivers side, but not sure where it goes after that.

The brakes dont seem any less efficient as they were before this occured.

any ideas, as i'm stumped not sure what to do next

Cheers

 

[zippy656]

checked if they need new pads?

 

[Midlander]

I Havent TBH, but have A complete set of brakes ro might just change them even if only to eliminate them.

incidentally, I've seen reference to A vacuum pump on the alternator butmine doesnt seem to have one there.
Looked at the electronic manual in Section EM-24 and it mentions one that's on the engine block, presume that's how mine is.

Does this pump do anything else other than brake vacuum?

 

[kitchenman]

is there a switch on the handbrake, could be that or does that have a different light
My Mav has 1 light for both

 

[Midlander]

is there a switch on the handbrake, could be that or does that have a different light
My Mav has 1 light for both

Checked all of that, took centre console out etc....switch works fine.
Mine's same as yours...one light does H/Brake, fluid & Vacuum warnings.

 

[rustic]

Try how many times in quick succession you can operate the brakes, before the light comes on as there may be a leak, and the vac pump is just keeping in front.

Another member had some recent welding around that area, and it put a pin hole in the vac pipe, this caused the same effect.

It could be a faulty vac switch, you can always check it with a bit of pipe, and suck it

 

[Midlander]

Try how many times in quick succession you can operate the brakes, before the light comes on as there may be a leak, and the vac pump is just keeping in front.

Another member had some recent welding around that area, and it put a pin hole in the vac pipe, this caused the same effect.

It could be a faulty vac switch, you can always check it with a bit of pipe, and suck it

Will have to get er indoors on that lol... seriously i'll need her to look at dash to see if light goes out.

what makes this relay click n clunk tho? it's behind the trim next to accelerator pedal on drivers side.

seems to do it when H/ brake switch is operated.

 

[Midlander]

Update.

Had the front wheels off to look at the Front brakes and the plan was to renew them, However, on disassembly I found that there's A Slider bolt on either calliper that's seized. So I cant get the new pads in.
Fortunately there's still some meat left on the original pads, so I Copper greased them up and reassembled.

I topped up the brake fluid and have managed to put the bloody warning light out.

However....I now have something else going on that's a bit odd.

Whilst driving the truck, there's A relay that clicks on and off. It also does it when the Hand brake is operated.

Fairly sure its something to do with the Central locking as it seems to affect the windows as well.

Could I have disturbed something whilst taking the centre console out yesterday to look at the H/Brake switch?

or have i inadvertently done something to the fob? Although the fob still locks, unlocks the car and it starts, drives ok..albeit with the relay clicking every now and again.

 

[Midlander]

Nuvva Update...

Right...Have sorted the Clicky relay.....I'd managed to trap a wire to the window switch harness.....Doh!

anyway... A quick snip, resolder the two ends and heatshrink sleeving and all is good. :thumbs

So.... all that's left is the Brakes....Callipers anyone? Mine have got the Seized pin problem.