MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - Brake light switch

The brake light switch on early cars is pressure operated by the brake fluid. My original one failed a couple of years ago but the new replacements are rubbish. I've had 2 new ones & they work at first but after a while you need more and more pressure on the brake pedal before the lights come on. Mine got to a stage where only an emergency stop would put the brake lights on.

However the solution is to embrace modern technology & use LED stop & tail lights. I bought a set from ebay last week & fitted them. They are a direct replacement for the twin filament bulbs & require no mods to the car. Because they draw much less current than normal bulbs across the switch the brake lights work properly again with light pedal pressure. Also, they react quicker. The ones I bought cost me £15 for the pair. Once the rear lenses are fitted you would not notice the difference. Buy red LED's as the white ones look pink through the lenses apparently.

Just a tip i thought i'd pass on.
G Britnell

Here's a piccy of the bulbs i used :-


G Britnell

Do you have a link to their web site? Cheers - Dave
David DuBois

These are the ones I bought :-


http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=220489090613
G Britnell

I bought a replacement pedal switch from my local motor factors and made a bracket to fit above the pedal. Cheap, simple, easily replaced.
Allan Reeling

Or fit a relay to take the load of the ordinary bulbs.
Mike Howlett

I used a relay with an arc suppressing diode. There are several links in the archives on that mod. At one time the LBC website in the US sold a better hydraulic switch which the last time I looked was listed. Search for brake lamp switches for MGB. This switch apparently has better contacts. The one I used before the relay/diode approach lasted at least five years. The ones from the auto parts stores lasted only days sometimes. Rather amazing that they couldn't handle the load of even a couple of low wattage brake lamps.

The LED is a nice solution though. I'll do that when the need arises.
Robert McCoy

The LED lamps look great, does one see them from the side also? I have heard they are rather directional? Ie need to be viewed from directly behind? Do the flasher bulb also work well, ie with the old flasher box still in place, or does one need to change this? Mike
J.M. Doust

The stop/tail LED's i bought have some of the diodes facing sideways so they can be seen from the sides as well. I cant comment on using them in the indicators as i've not tried them myself.
G Britnell

On my '67 GT, I use standard light bulbs with the addition of an LED cluster mounted on the rear of the ceiling to mimic the placement of the middle brake light on modern cars. I also had trouble with the hydraulic switch until I got one from Ron Francis Wiring. I've been using the Ron Francis switch for about six months with no complaints. -G.

http://www.ronfrancis.com/prodinfo.asp?number=SW%2D32
Glenn G

Hi,

Check the following article I wrote and that is on Paul Hunt's website. It describes an alternative way to fit a brake light switch.

Herb

http://www.mgb-stuff.org.uk/saga19.htm
Herb Adler

Whilst on the subject of LEDs are there any that we could use for dash guage illumination?
Many thanks
Peter Malkin
Peter Malkin

Hi Peter,

I'm in the process of playing with LED strips, for this purpose. They come in 1m lengths and can be cut to length, provided that there are 3 LEDs per length.
I haven't got as far as installing them yet, having just got a spare speedo to play with.

Check out this website of Melbourne based company.

www.worldofthought.com.au

Herb
Herb Adler

Thanks Herb - I'll check it out.
Peter
Peter Malkin

You need to be aware that LEDs as a retro-fit are probably illegal for road use in the UK (they are frequently advertised as being for show and off-road use only) which can invalidate your insurance.

UltraLED used to make a multi-element direct replacement for gauge lighting bulbs which gave a slight improvement (see http://www.mgb-stuff.org.uk/electricstext2.htm#uprate) but they are no longer available. There is a source of single-element LED replacements but I have found they are no better than incandescent - unless your incandescents are old and silvered inside of course, in which case new incandescents will be just as good, cheaper, and your dimmer (ho ho) will still work.
PaulH Solihull

This thread was discussed between 17/05/2011 and 26/05/2011

MG MGB Technical index

This thread is from the archives. Join the live MG MGB Technical BBS now