Firstly, the brake fluid level warning light is an SVA requirement, isnt it?

I'm sure it is, and I guess there was a switch built in to the original cylinder, but how has anyone installed one using aftermarket cylinders?

I was thinking just put a float switch inside the cylinder, or is there another solution?

If anyone has any pictures that would be a great help!! Cheers

hi Stuart,

Yes the brake fluid level warning light is a requirement for SVA.
It also comes on when the handbrake is applied via a switch on the handbrake.The light serves a dual purpose for handbrake on and fluid low.
The 'switch' for the fluid level is mounted in the cap of the brake fluid resevoir in the form of a float switch under the cap.
There is also a press button moulded into the cap which allows you to 'test' the switch (aftermarket resevoir). The after market master cylinders will have no influence on the fluid level warning light unless of course you have a leak in which case the reservoir level will go down and your warning light eventually come on.
If you are using an aftermarket loom (as I did) then there should be two wires which connect to the cap of the brake fluid resevoir and another for the handbrake switch. They'll be clearly labelled (hopefully).
As far as SVA goes, the inspector usually just tries the handbrake in the on position to check the brake fluid warning light is working, however, mine did press the resevoir button as well.

Hope this makes sense

Dave

Thanks Dave,

Only problem is that my reservoirs are built into the cylinders. However, I've just discovered that the switch cap from my mk5 escort fits, so I'll get a replacement one of those and use that... problem solved!

Only other question is, do I need one for both cylinders???

Cheers,
Stu
Rescued attachment mcs.jpg

As Dave says really apart from IMO the Low Level Warning Light ought to be fitted to both reservoirs, purely for your own safety and peace of mind. Easy job if you can use an OEM Cap to fit your particular reservoirs. Wire them both in parallel and you're sorted.

Steve

Agree with Steve, both caps should be fitted with warning light switches.

My after market reservoir serves both master cylinders, so only one cap needed.

cheers.

Dave

They will want to be in series won't they for either switch to set off the light?

No - parallel - so either switch connecting will make the circuit.

If they were in series then you'd have to have both on before the light would come on.

David

i always take in mind that the christmas tree lights are in series..


you undo one light and everything goes off thats tipical series connected.

a normal wall socket is typically parrallel...

Tks

Ah - I see, that's because I thought it was the switch opening which caused the light to come on - I'll get my coat.