brake lights

[steve c]

hi, my brake lights are a bit erratic, they work most of the time but them seem to stop working, then all is back to normal. all bulbs are ok, all wiring is new and connected correctly, i suspect the switch, but if it works ten or so times , why would it then stop for a few times, then back to normal, any thoughts would be helpful, regards steve

[katy]

If the wiring and lamps are good then it's most likely the switch. Try a new one, they're not very expensive.
BTW, how old is the existing switch?

[JOWETTJAVELIN]

Mine is 56 years old and still going strong.

Planned obsolescence was unheard of in Britain at that time.

[bmcecosse]

Loose/bad connection? If you join the two wires at the switch -do the lights come on EVERY time?

[steve c]

if i join the wires at the switch, yes the lights work every time, rejoin the switch and they are intermittant again. i have a new switch to fit, but looking at how its mounted and all the brake pipes there, i am absulutly dreading trying to remove the old one, any tips on removal. regards steve

[bmcecosse]

Unscrew and discard - keeping a finger over the open end - then quickly remove finger and screw in new switch! Have a cloth or two round about to catch any leaking fluid - but you can minimise this by fitting the master cylinder cap with a piece of plastic bag underneath - to seal the chamber.. Should discourage any fluid rushing out....

[Dean]

Like Bmc says above have a cloth handy and a spare finger. I did replace mine recently..... I unscrewed slowly removed the old switch and screwed the new one in without losing any fluid. I guess as there was no pressure, I was fine... just don't pump the brakes before the fitting, leave overnight for the shoes and pressure to fall away slightly.

[steve c]

its not the loss of fluid that bothers me, its trying to unscrew the switch without fracturing a brake pipe

[chrisryder]

Try mole grips clamped onto the 4-way 'T' piece to stop it turning.

[bmcecosse]

It shouldn't be 'that' tight. Just have a go - if it starts to unscrew, then nip it up and get everything ready for the swap.

[brucek]

Maybe start by ensuring the 3 way union is not loose. Then try to release the old switch - if it doesn't loosen before the union starts to rotate, use the mole grips to brace it. As BMC says, it shouldn't be that tight so you should be fine. He who dares Rodney, He who dares....

[mike.perry]

Hold the bolt under the "floor" with a spanner whilst you undo the switch

[bmcecosse]

The wee bolt just passes through the 'T' piece -so it's not much use at stopping the thing spinning round.

[steve c]

well, i got the little bu--er off, but it realy was tight, had the tee piece braced in all directions, not tried it yet as the rear hubs are still in bits regards steve

[tomas.geoghegan]

Hi Did a brake switch with mold grips was a right litle Bar----d
NOT Easy
WELL DONE!
Tomas

[C6Dave]

if i join the wires at the switch, yes the lights work every time, rejoin the switch and they are intermittant again.

I was on a 'Drive It Day' run today and when we got to the halfway coffee break I was told that my brake lights weren't working by an MG driver, who suggested it may be the switch.

Having done the test as above when I got home with a bit of wire, they do in fact work so it's not double bulb failure

Tried again from in the car and unless your pressing the brake pedal pretty hard, there is no light, press it hard though and yes they do come on.

For confirmation, I assume that the switch is not 100% then and need to order a new one to replace it?

Best place ESM or ................

[bmcecosse]

MOT wise that would pass - as far as I know there is no minimum pressure to be applied to the pedal to bring on the lights. It would however be wise to change the switch - but some of the modern replacements seems to be decidedly unreliable. New Old Stock would be a better bet, and i think some have used a Landy item with great success.

[C6Dave]

Thanks. As you say it would be 'wise' to change it as I don't want someone running into the back of me......

[bmcecosse]

Just use the 'slowing down' hand signal!

[MarkyB]

That would just distract them!