Thread: Amazon: - Brake light switch
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Old May 15th, 2015, 10:00   #5
swedishandgerman
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I really like the principle of the other type of brake light switch, but I would like to consider the older type because I don't think they're as bad as. Yes, they do have significant reports of early failure and I agree that the newer version with a switch on the brake pedal has obvious benefits of the brake lights coming on much earlier.

However, I feel quite sure that the actual reason for early failure of replacement switches are not to do with the switches themselves, even though they are quite flimsy! My thoughts are based on the amount of current running through the switch as follows: Firstly, when I have towed without a relay in the system, the switch quickly burnt out. The other thing is this: those back light units deteriorate quickly and corrosion builds up around the bulb holders, connectors and earth connectors, so the current required to make the bulb light is high. As well, the wires fray, so if there's a short, the current is extremely high.

A good session back there cleaning up all the connectors, earths and bulb holders together with a fresh set of bulbs will soon brighten things up back there. That leads onto the very well discussed thing on this forum about re-painting the rear light reflectors or covering them in high reflective aluminium tape...

ALL the current for the brake lights go through that tiny little switch - 2 x 21w bulbs. Add a trailer and/or an extra brake light.... You see where I'm going. It's a flimsy switch. As such a really simple upgrade which will significantly increase the longevity of it would be to add a simple relay straight off of the fuse box with it's own fuse would ensure as much current as possible will go back to your brake lights AND the only current running across the switch would be that required to activate the little switch in the relay.

This is a well used modification in the air-cooled VW world which has the same flimsy brake light switch.

All said, none of this is a good as a switch down on the pedal!
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Last edited by swedishandgerman; May 15th, 2015 at 10:56.
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