Gen 2 Brake Light

Hi All,
Suddenly my 2006 Tuono has no brake light.
I have disconnected and isolated front and rear brake light switches. Testing with my multimeter seems to say they work.
I can't see how to investigate the bulbs (I think LED's) in the rear light unit.
Any thoughts on this?
Regards, Bern.

Back again. Another question, is the tail/brake light repairable, or is it just replaced when faulty?

Regards, Bern.

I managed to repair mine for my MOT last year. Depends how patient you are?? The unit is glued together, which is the hard part that needs patience. After this, I took apart to find that a transistor / regulator had come away from the circuit and was lose. Is there a small rattle at all when you shake the unit?
If you are ok at soldering and have patience you can fix it. I'd even be happy to post you the part (if this is the cause). I bought a box of them for 12 quid and have more than I'll ever need.

EDIT: Oops, sorry, just noticed you are in Australia. The postage may be a problem

These are what I bought: Amazon.co.uk

Part that had come lose:

So soldered in a replacement and all was good. If you have zero lights (either idle rear OR brake) then this is the most likely culprit. From memory, it keeps the LED's dimmed with 4v until you press either brake and then you should get 12v.

Thanks SD. That's great info. I didn't even know they were LED's! Great to learn how the system works. From your info, am I right to think the assembly has a bank of LED's which are always on, and the brake light is effectively a boost to the system. Sounds clever to me.
I have a light at all times. There is no boost when I press either the foot or hand brake. Do you think this would indicate that the light assembly is fine, but there is an issue between the original power source for the brake lights and the light assembly itself?
Again, thanks for your help. Regards, Bern.

If you look under your tail unit, you will see the plug going into the rear lights. According to the diagram: Blue = Earth. Green & Yellow = Switched live (brake light signal). Green & Grey = Permanent live (rear lights).
If you are able to test that these work with a mulitmeter we can figure out hopefully where the problem might be? If these are all working, then the problem is inside the tail unit.

Fantastic SD! I will investigate when I get over today's adventure. I had a thumb reconstruction.

Your suggestion looks logical and simple, so I will get onto it soon and report back.

All the best, Bern.

Back again SD. They said my thumb would take a while. So it panned out!
Yes, I have power for the brake light to the last connector before the tail/brake lights. At this connector the brake light appears to be working off the switch. 11.00+ volts when the switches are on.
I suppose the issue is in the brake unit. What do you reckon?

Hi Beernard

Definitely seems to be inside the light unit itself then.
If you feel you can manage it without hurting your thumb, then the glue around the light unit needs carefully "cutting" out with a sharp craft / utility knife as much as possible (nice thin blade).

Obviously, removal of the unit is required first and this is really easy. You should be just about able to squeeze it out once undoing the screws.

I also used a hair dryer to help heat up the plastic once I'd removed as much glue as I physically could - but I'm in chilly UK and this was in back in September. I didn't want to risk breaking cold brittle plastic. I'm sure your weather will allow you to skip this step You can then prize open the light unit to get at the gubbins.

The way I see it, the unit is dead - you have nothing to lose (except a thumb ) in taking this unit apart. They are classed as replaceable, so any attempts to repair it are always worth it in my mind. My repair cost hardly anything, where as a 2nd hand unit for me on ebay was pretty pricey - a brand new one even pricier.

I would remove the light unit, and give it a shake, see if you can hear any lose components - I'd be surprised if you don't. The light units seem to shake themselves apart with vibration.

Let me know your thoughts and findings and good luck

Thanks SD. Will do.

Gday SD. Hope all is well. I'm starting to use my thumb a bit more, so its time to remove the tail light for inspection. How do you remove the fasteners in the attachment? They are unfamiliar to me.

Thanks.

They can be a bit fiddly. I personally never had to remove any to remove the tail light? I undid the screws and managed to squeeze it out from inside. However, if you feel you cannot do that, then maybe this video will help:

Thanks SD. I'll have a go at wriggling the unit out tomorrow. I can put a bit of pressure on my thumb now.
I also watched the vid, so I have a better understanding of the fasteners. Thanks.
I'll let you know what happens!

Gday SD. I got the unit out and opened it. Nothing loose. I can see the 3-pronged part but it can't actually move. It is pop-riveted in. I'll attach a pic. Looks really tricky to deal with, when you consider my skills!
I think I am beaten. What is your take?

Hi Beernard

Apologies for the late reply. I missed the notification.
Yours is actually a slightly different design to what mine was by the look of it. All of the electronics were stacked inside of the silver part of the light and screwed in, so yours is even easier to work with by the look of it. Also, your transistor is screwed down secure, where as the design in mine has nowhere to screw to. So is definitely a revision on from mine.

You have a multimeter so it shouldn't be too hard to figure out tbh.

First off, plug back into the bike to get some voltage to it.

Trace the negative and the two lives and see where they go. I no longer have my Tuono, so I can't be of much help tracing the wiring inside the gubbins I'm afraid and the diagram doesn't who the inner workings.

At this point you are checking for where the 12v stops essentially. If the 12v is present at one of the transistor legs but the pull up leg doesn't fluctuate when pressing either of the brakes, then the transistor needs replacing.

Let me know how you get on.

Good luck.

Hi SD,

Thanks again for your ongoing support. I'll have a crack and let you know what happens.

Regards, Bern.

Gday SD,
Thanks for all your assistance and time during this adventure.
After I disassembled the tail light, I managed to break a bank of LED's
I then found a new Chinese item on Ebay for $65. I bought it, installed it and all is fine.
Thanks again for your kind advice and time.

Regards Bern.