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View Full Version : TR6 Brake light on -reasons?



ichthos
10-07-2014, 12:22 AM
The brake light went on before I rebuilt the front brakes. There was some corrosion on the cylinders. I rebuilt them wit stainless steel pistons. After I bled the front brakes, and took my car out for a test drive, and the lights went out eventually. Today when I stated the car the lights went on and didn't go off. Any ideas on what I need to check? Do I just need to bleed the brakes better? Master cylinder need to be rebuilt?
Kevin

TR3driver
10-07-2014, 01:24 AM
AFAIK all TR6 use a mechanical brake light switch. The switch is normally closed, so the pedal has to hold the switch plunger depressed to keep the brake lights off. Check the pedal for freedom of movement, return spring in place and the switch adjustment. Might be a bad switch or a short somewhere, but those are less likely IMO.

3798j
10-07-2014, 07:09 AM
Is it the brake warning light that is lit?
If it is, the PDWA is signalling it's not centered. After doing the brake work you've done, there's a couple of possible reasons the warning light is still on. You could have a problem or the PDWA might just need to be re-centered - there's a procedure.
Reading this you'll get an explanation : https://www.buckeyetriumphs.org/technical/Brakes/Theory/Theory.htm

dklawson
10-07-2014, 07:44 AM
As above... are you saying...
1) "The car's brake lights are always on"
or
2) "The brake warning light is staying on"

1) = pedal switch as Randall said,
2) = PDWA or (depending on the age of your car) parking brake switch is stuck on.

ichthos
10-07-2014, 10:20 AM
It is the brake warning light that comes on. Rebuilt the pdwa a few years ago, but I will check out the article on resetting it this weekend. I will go through the other suggestions too. Many thanks, Kevin

poolboy
10-07-2014, 12:56 PM
If the lamp is glowing brightly, then the PDWA switch (or wire) is grounded.
If the lamp is glowing dimly, the OP warning lamp should also be glowing dimly. In that case, check out the OP warning switch.
In case you have trouble differentiating a bright from a dim BRAKE warning lamp, disconnect the PDWA wire and ground it to the frame or the brass PDWA itself...That will make the BRAKE lamp glow at full brightness.

TR3driver
10-07-2014, 07:24 PM
Apologies to all, it dawned on me later that he was talking about the PDWA lamp rather than the rear brake lights. But by then we were already packed and back on the road.