These are easy to change, but they are not a serviceable item so you'll need to purchase the entire tail lamp. I'd have to check the schematic, but there is a chance left and right may be fused separately. Checking this would be a better place to start, then go the expensive route only if necessary.
I'm assuming it's the whole lamp that's out, not just some individual LED's?
The park lamps are fused separately, left and right, in the underhood fuse block. The stop lamps are fused in the right rear fuse block but both left and right are on the same circuit. If absolutely nothing works (brake, signal, park) then you have either a bad tail lamp assembly or bad wiring. My next step would be to pull the connector off the tail lamp and check voltages.
Cavity 'D' is ground and will be a black wire.
Cavity 'A' is the park lamp supply voltage and will be a purple wire.
Cavity 'E' is the brake lamp supply voltage and will be a light blue wire.
If you look very closely at the connector, you should see the cavity letters embossed in the housing. This will help you to identify the cavities.
With the park lamps on, you should have roughly 12 volts when measuring across cavities 'D' and 'A' (with the engine off). When someone steps on the brakes (car must be running), you should see about 13-14 volts when measuring across cavities 'D' and 'E'. If you have proper voltages, your tail lamp assembly is defective and needs to be replaced. If you don't, you have a wiring problem that will need to be investigated.
It is unlikely to be a short or it would have blown a fuse and neither side would work. If there is a problem with the tail lamp, it is most likely an open circuit due to corrosion from moisture intrusion. It's also possible there is a problem with the logic in the lamp.
Originally Posted by Cadjiek
Do they still use a switch at the brake pedal? Could that be the problem? I don't know if he got a good reading from cavity E or not.
Yes, there is still a brake lamp switch. Since one side works, this rules out the fuse, switch and relay (located in the right rear fuse block).
If there is any question about the supply voltage to the connector, I would double check it again. The likelyhood of wiring is small because the wire runs directly from the rear fuse block to the connector and does not pass through any other connectors. Also, none of the wiring is exposed to the exterior of the car.
I guess what I'm saying is "correct" troubleshooting technique dictates checking all wiring up to the lamp assembly prior to replacement. The tail lamp is quite likely the problem but also expensive. Rule out all other causes before spending money on costly parts.
Aren't we forgetting something, the brake lights signals,come through the multi-Function switch,
to cut out the brake signal, and blink the appropriate, tail light ?
I am NOT saying ,the Whole light is good or bad,
the voltage readings "NEED" to be read at the connector as:
ddalder suggests above !
Both turn signals work as they should, both tail lights work as they should, and the left side and center brake lights work as they should. It is only the right side brake light that is not functioning.
Also I have noticed on the right side tail light one of the individual LED's is intermittent.. sometimes it's on sometimes it's off.