[cota348]

You can pull fuse #1 which is the DRL/park-sidelights only - to observe whether the LED unit dims or remains the same in brightness. That will confirm the brake lights or switches are the root of your trouble. Connectors will rarely present problems of a short circuit nature, more likely to have a fractured wire, open circuit or high resistance crimp termination.

3 wires go to the brake/park LED, Yellow for park/run (DRL) and green/violet for the stop/brake LED plus black for ground/frame. That green/violet wire goes directly to the rear brake switch with front and rear brake switches effectively wired (albeit convoluted), in a parallel configuration. It's the same part# for many Triumph models current and not so. I'm led to believe the OEM item is not all that impervious to the ingress of dirt and water where our brothers over on TriumphRat have reported a few posts on the same premature failures.

Triumph MICRO SWITCH,BRAKE,SPDT Part # T2024932
Fits Bonneville, Bonneville Bobber, Bonneville Speedmaster, Speed Triple, Street Cup, Street Scrambler, Street Twin, Thruxton, Tiger

View attachment 52584

Thanks for pointing me in the right direction, I will get back with my findings

 

[Retro Rocket 48]

Since you're not the original owner you wouldn't know if the previous owner made some changes to the indicators or brake light and changed everything back to stock before selling. If this is the case then it's possible that the wiring was mixed-up.

On that note, I wouldn't want to be the next owner of my ride, not that I would consider on-selling my BB, however being a techo I just cant help with compulsion but to tinker and modify, lots of ancillary electronics behind those air-boxes. I do though redraw and amend the circuit diagrams, nothing committed to my dimming memory.

 

[Stumac]

Crikey - this is one mixed up thread.

Can you just confirm the following

Has the fault arisen during your ownership - or was it there from the start, and, are you certain that the brake light is on all the time, as opposed to not working at all as your only confirmation of this is that "it looks pretty bright".

 

[BobberNoir]

Maybe I missed this somewhere, but have you tried to just replace the bulb?

 

[Chico]

Maybe I missed this somewhere, but have you tried to just replace the bulb?

I believe the brake light has LED's and can't be replaced.

Chico

 

[Bobber-Bomb]

Maybe I missed this somewhere, but have you tried to just replace the bulb?

It’s not a Harley, the rear light and indicators on all models are LED!

 

[Chico]

It’s not a Harley, the rear light and indicators on all models are LED!

Modern HD's are also LED's. You just like to pick on Harley.

Chico

 

[Bobber-Bomb]

Modern HD's are also LED's. You just like to pick on Harley.

Chico

Yes, and they’re super large because of out of date US type approval rules! Have you seen what the US regulators have forced Ducati to do with the indicators on the American spec version of their new Monster? 😫

But no I’m not anti-Harley, I’ve owned them in the past and I get why people love them. But you’ve got admit up until very recently they’ve been slow to modernise, which I guess is all part of their charm.

 

[cota348]

Crikey - this is one mixed up thread.

Can you just confirm the following

Has the fault arisen during your ownership - or was it there from the start, and, are you certain that the brake light is on all the time, as opposed to not working at all as your only confirmation of this is that "it looks pretty bright".

I am not sure, I think the light was always like it is right now.

 

[cota348]

Thanks for pointing me in the right direction, I will get back with my findings

I pulled the DRL fuse and no light, so I thought that the brakes do not light the brake light, but then I saw the wiring diagram and it seems to me that the line with power is common to the DRL as well as the brake lights, so by taking the fuse out I take the power out of the brake lights too.

 

[cota348]

On that note, I wouldn't want to be the next owner of my ride, not that I would consider on-selling my BB, however being a techo I just cant help with compulsion but to tinker and modify, lots of ancillary electronics behind those air-boxes. I do though redraw and amend the circuit diagrams, nothing committed to my dimming memory.

Although I am not the original owner, I can tell if the lights were tinkered or not and this set is original.

 

[Retro Rocket 48]

The brake/park sealed unit comprises an integral 2 x LED array with a centre tap common to fame/ground. This version of the wiring diagram shows older twin filament incandescent bulb. The DRL fuse supplies power to the park and licence plate LED's only. As for the brake LED, it derives 12volts power via the rear brake switch and Green/Violet wire.

If you pulled the DRL fuse with the result of no rear lights at all, then I suspect the brake light LED array has gone down.

 

[atomsplitter]

You might be looking at getting a plug and play replacement and test the circuits. The schematic shows the DRL comes from the ignition switch position so if the tail light lights when you switch on, then the brake light is toast. You tested the switches at the front and back actuators and they are working so if the lamp doesn't brighten the brake light must be bad. I'd replace the unit and remove any doubt myself.

 

[cota348]

The brake/park sealed unit comprises an integral 2 x LED array with a centre tap common to fame/ground. This version of the wiring diagram shows older twin filament incandescent bulb. The DRL fuse supplies power to the park and licence plate LED's only. As for the brake LED, it derives 12volts power via the rear brake switch and Green/Violet wire.

If you pulled the DRL fuse with the result of no rear lights at all, then I suspect the brake light LED array has gone down.

View attachment 52611

I suspect the same, but that light is LED which should last a lot longer.

 

[cota348]

You might be looking at getting a plug and play replacement and test the circuits. The schematic shows the DRL comes from the ignition switch position so if the tail light lights when you switch on, then the brake light is toast. You tested the switches at the front and back actuators and they are working so if the lamp doesn't brighten the brake light must be bad. I'd replace the unit and remove any doubt myself.

The unit is the whole unit since it is an LED unit with rear lights and brakes lights in the same unit, which costs $130.

 

[Chico]

Many members of this forum have replaced the stock brake light, perhaps one might be willing to part with the original. List your request in the wanted section.
Conversely, this is a perfect opportunity to replace the brake light with an after market unit.

Chico

 

[Retro Rocket 48]

The LEDS are very reliable and enduring, however it will more likely be a mechanical failure on the PCB where a pin-through has gone O/C, a 'dry' termination, or gone high resistance.

Maund Tail Tidy Polished Aluminium or black matte case, red or smoke lens options.

 

[atomsplitter]

The unit is the whole unit since it is an LED unit with rear lights and brakes lights in the same unit, which costs $130.

A used one should be less, I found a T2702070 for $79.00 (sold of course), so if you can't talk someone here out of their unit, they will come up for sale on the web from time to time. You could also look at this for $60.00 to test you unit: Triumph, Bobber, Speedmaster custom tail light | eBay

Good luck.

 

[Taurus]

I second the suggestion of a Maundspeed light. They are beautifully finished and really suit the Bobber. They can sit on the stock light mount

 

[cota348]

Hi guys, an update (sorry being away). II just dismounted the taillight and checked there is a voltage between Yellow and Black (DRL) but I don't get anything from Green/Violet and Black when I press the switch (front and rear).
The chances for both front and rear brake switches going bad at the same time are minimal, what else could be wrong?