[tomellis]

I am new to this forum. I did a search on this topic but did not find anything, but I may not have looked in the right place.

I have a 2004 Prius, and recently discovered that the right side brake light is not functioning. I thought that it would be the usual easy fix that I have had on previous cars, just a matter of accessing the back of the light assembly and replacing the faulty bulb. I was quite surprised to discover that not only is there no easy way to access the brake light, but there were no obvious wires that went to the uppermost part of the light assembly, where the brake light is located.

Thus far I have only looked through the access panel (which allows easy replacement of all the other taillight bulbs), but I have reached all around the light assembly and felt no other wires entering the assembly.

Before going any further and removing interior body panels to get more access I decided that it would be smarter to first consult with people who have already encountered and dealt with this problem, rather than just diving in with no real idea what I might be getting into.

So what the heck is going on here? Is it even possible to replace the brake lamp? And where are the wires that control the brake light?

I really appreciate any help/advice that anyone can give me. I'm no pro mechanic, but I have always been able to handle just about anything that has gone wrong with all the cars that I have owned, so I hope that I will be able to deal with this as well.

 

[Easy Rider]

I have no experience with that specific model but you do know that the tail light/brake light/turn signal often share a dual element bulb.....right ?? Thus there aren't any extra wires just for the brake light.
Is the turn signal not working on that side too ??

You probably just need to study the situation a bit closer.

And if you visit the parts department of a Toyota dealer, they might show you the diagram of the rear light assemblies.

 

[tomellis]

I have been doing more research on this and have found out a bit more. The brake lamps are LEDs, and are NOT made to be user replaceable. Completely separate from the other lamps in the taillight assembly. To replace them you have to replace the ENTIRE ASSEMBLY! But they are also supposed to have a crazy long lifespan, and are likely not really dead. More likely that there is a wiring issue of some kind.

I have yet to find a good wiring diagram for the brake lights, and am still puzzled as to how the heck the brake light even receive power, as I cannot see any wires running to the top of the assembly. I am still hoping that someone in this forum has had the same problem, and can tell me how they dealt with it - hopefully not just letting the dealer fix it!

 

[Easy Rider]

The wires to the LED brake assembly might be a ribbon cable molded into or glued onto the plastic housing.
At any rate, there has to be a connector somewhere.

Once again I suggest visiting the parts counter at a dealership and asking to see the diagram of how the rear lights connect up. You are likely not the only person who has had this problem. They might even be able to give you suggestions on what the problem might be.

If you do end up needing the whole assembly, you might be able to get one from a salvage yard a LOT cheaper.