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interesting idea for brake fluid warning light test?
blakep82 - 20/4/09 at 07:51 PM

yes it could easily be done by using the handbrake switch...

the other accepted method is to use a seperate push switch on the dash to test the light. i had one of those on my old mini and my cortina. i never felt the need to test the light though. so i'd never know if it worked or not.

a way to make the light come on automatically to test when you start the car would be ideal, sooooo

what if i was to wire mine into the starter solenoid circuit? that way whenever i push the starter button the warning light will test itself and come on.

can anyone think of any issues with this?

speedyxjs - 20/4/09 at 08:07 PM

Sounds ok to me. Your just using the same push button to start the car as you are to test the brake warning light

blakep82 - 20/4/09 at 08:09 PM

yep, and it tests the light every time you start up.

just thought the might be a reason why no ones done it before. like, do you have to be able to test at ANY time (inc when the engine's running)
but you can test when the cars moving really...

iank - 20/4/09 at 08:13 PM

If you can arrange it you'll be fine according to both SVA and IVA wording - you may need a relay to change from switched live to switched earth depending on your solenoid wiring.

quote:
IVA draft 3.2
The hydraulic system failure warning lamp must be secure,
operational, visible during daylight and darkness from the driving
position, identifiable (ie labelled in a recognised form – see diagram
1 for an example) and fitted with a “test facility” that enables its
operation to be checked from the driving position without opening
the reservoir.

blakep82 - 20/4/09 at 08:15 PM

i've not got any relays in the solenoid circuit, but given a bit of thought on the wiring front, it might work!

bigfoot4616 - 20/4/09 at 08:23 PM

whats the point though? isn't the light test another of those things that are done just for sva and never needed again?
in which case i would keep it simple and use the handbrake, then there's no need for an extra switch that never gets used

nitram38 - 20/4/09 at 08:41 PM

Do it on the handbrake and you get a warning that the handbrake is on too.

blakep82 - 20/4/09 at 09:06 PM

quote:
Originally posted by bigfoot4616
whats the point though? isn't the light test another of those things that are done just for sva and never needed again?
in which case i would keep it simple and use the handbrake, then there's no need for an extra switch that never gets used


i'm not sure thats the right view to take on it although i'm sure we all do

i knew the mention of the handbrake switch would come up, I've not got any other wiring near where my hand brake will go. i put all my wiring down the passenger side of my car, on the thinking that there will always be a driver when the cars being driven, but there won't always be a passenger, so keeps it more out of harms way. exhaust has to run down the tunnel so brake lines and wiring goes inside the cab.

also, my hand brake has to go to the right of the passenger seat due to space.

hand brake switch is tried and tested, but seems like a lot of extra cabling to run, and put in flexi tube, and drill the chassis to clip it all down, where i could do it all in the dash.

like bigfoot says, theres no point in putting an extra switch that won't get used, so thats why i decided against a seperate 'push to test' switch on the dash, as i'd never use it, and the light would go untested

this way, the starter button is already there, and its a sure fire way of testing the light on every start-up.

i think i have tried pulling away while the hand brakes been on a few times recently, so a warning light is a good idea, but hasn't done me any favours before

blakep82 - 20/4/09 at 09:22 PM

the testing of the light is a safety thing. i'd rather it did it automatically than not at all. the way i'm thinking is the easiest automatic way i can think of.

blakep82 - 20/4/09 at 10:42 PM

Description
Description

i think this could work
obviously i meant to put the solenoid after to start button

bigfoot4616 - 20/4/09 at 11:29 PM

i think you would need to use a relay there. the start button is switching live, you need earth for the light.
a savage start switch would work, use the other side of the switch for the light

damajin - 21/4/09 at 06:01 AM

Just to add another opinion to the mix...
If you are really dead set against using the handbrake switch (which in your case I can see the why) couldn't you just wire the warning lamp into the same circuit as the alternator no-charge lamp (or even instead of it if you don't intend to have a no-charge lamp), this way the lamp gets tested as soon as you turn the ignition on and will go out once the engine is running. This is, I'm pretty sure, how most production cars do it.

D

mad4x4 - 21/4/09 at 06:40 AM

quote:
Originally posted by blakep82
Description
Description

i think this could work
obviously i meant to put the solenoid after to start button


That would blow afuse if the float switch was closed and you pushed the |"Start button"

britishtrident - 21/4/09 at 07:40 AM

Really would best to stick with the handbrake switch method

scudderfish - 21/4/09 at 09:04 AM

quote:
Originally posted by mad4x4
quote:
Originally posted by blakep82
Description
Description

i think this could work
obviously i meant to put the solenoid after to start button


That would blow afuse if the float switch was closed and you pushed the |"Start button"


Surely not being able to start the engine if you have no brake fluid is a good thing!