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I seem to have lost my Brake Lights?
The Venom Project - 3/6/12 at 05:45 PM

I have tail lights, indicators but for some reason I have lost Brake Lights, they were working before, any ideas? checked all the connections, I can only think the brake light pressure switch might be buggered? Any ideas would be most appreciated, won't be going to Newark in it if I have no brake lights. Everything else seems fine, checked fuses, what the hell can it be?

This is an R1 engine with original loom just extended, and everything was fine.

Cheers

Nick


rodgling - 3/6/12 at 05:47 PM

Use a multimeter to test the pressure switch?


perksy - 3/6/12 at 05:56 PM

Check the brake pressure switch

Might be worth considering fitting a micro switch instead


AdrianH - 3/6/12 at 06:01 PM

I would also suggest the pressure switch is at fault. Probably high resistance, try lots and I mean hard pedal pressure to see if the lights will come on.

The contacts can soon burn out, as the switches are not as good as they used to be made in the original mini's etc.

If it is the switch consider helping it with a relay so the relay takes the switching current and not the pressure switch. The typical current drawn is 3 to 3.5 Amps so can soon arc the contacts.

I found this of help from an MG forum
switch linky



Adrian


[Edited on 3-6-12 by AdrianH]


The Venom Project - 3/6/12 at 06:01 PM

Just tested the rear brake light switch output and find when the pins are shorted together it works the brake lights, therefore its looking very much like a faulty Hydraulic Brake Light Switch..... How very annoying indeed, its not even a year old

Cheers for the responses guys, Nosecone coming off tomorrow to get a closer look.


AdrianH - 3/6/12 at 06:04 PM

The other question is have you used an M10 fine thread one or a 1/8th NTP threaded one?

The metric ones are easier to get now.

Adrian


The Venom Project - 3/6/12 at 06:12 PM

I seem to think its an M10 one, but now considering fitting a conventional Brake Light Switch like a micro switch, as its been in use for about 2 months so its pretty shoddy if its packed up already. Where its located I cannot easily remove without taking the nose off, I would have expected it to last much much longer.

Will know for sure tomorrow, was hoping for a nice relaxing long weekend, the joys of owning Kit Cars


The Venom Project - 3/6/12 at 06:17 PM

Just found one of those old style Moss Security bonnet switches, which I think will do the job fine from a suitable bracket I will try and make tomorrow,


perksy - 3/6/12 at 06:18 PM

Make a bracket up and fit a micro switch, Solder some tails on the excisting wires if you need to lengthen them

It'll be a lot more reliable and less hassle in the future


Snuggs - 3/6/12 at 06:21 PM

How is the switch orientated ?

If the terminals are pointing up then an air bubble can collect in the inlet of the switch.


lotusmadandy - 3/6/12 at 06:26 PM

My pressure switch stopped working after my sva.
I found that it had air trapped in the opening and
it wouldnt allow the connection to be made.
I turned the t upside down so the switch pointed at the
floor,it solved the problem.

Just a thought...........

Andy

[Edited on 3/6/12 by lotusmadandy]


bob - 3/6/12 at 06:32 PM

As above,exactly the same happened to me.

Although i didnt move the orientation of the pressure switch, i just bled the brakes properly to sort the problem.


Peteff - 4/6/12 at 08:04 AM

If you're replacing the switch with a mechanical one remove it and fit a bleed instead.


iank - 4/6/12 at 08:18 AM

If you persevere with the hydraulic switches buy an OEM VAG one. See http://www.locostbuilders.co.uk/viewthread.php?tid=169898

[Edited on 4/6/12 by iank]


MikeRJ - 4/6/12 at 12:32 PM

I don't understand the theory behind air stopping these switches working. Pressure is pressure, and the air will always be at exactly the same pressure as the brake fluid. I suppose if there is enough air that you wouldn't be able to generate sufficient pressure to operate the switch, but then you wouldn't have any brakes either.