Stereo & Electronics - Tail Light Issues

I tried searching but couldn't find a thread that addressed this...

I am having issues with my passenger side taillight. When I hit the brakes it does not light up, but when the blinker is used.. the light works just fine. When the headlights are on the lights work in the dim setting and when the lights are on and the blinker is used, it works fine. So I've ruled out either of the filaments of any of the lights being out.

This leads me to believe it is potentially a relay problem somewhere. Anyone have any ideas?

Thanks!

Since bulbs are oh so expensive [/sarcasm] I'd replace it anyways and rule it out comepletly.

All bulbs including each of their filaments seem to be working fine... I don't think it's a bulb problem, but you're right, they aren't that expensive and I could try it.

Assuming the bulbs are okay, it sounds like you have a problem with your turn signal switch. We can eliminate the brake switch because the left side still works and there is only one brake switch for both sides. The turn signal switch takes power from the brake switch and passes it through to each of the taillights through two separate output wires. When the turn signals are on for one side the T/S switch diverts the power input for that side to a wire coming from the flasher but continues to pass brake light power to the other side. It sounds like someplace inside the T/S switch the connection to pass through the brake light power to the right side isn't working.

To test this you'll need a test light with a sharp probe so you can check for power while still leaving everything connected. Find the 11-pin black connector attached to the right side of the steering column. It has only 10 wires in it with an empty spot at one end. At the other end is a light blue wire that carries the power from the brake light switch. Test that you get power there whenever the brake pedal is pressed (you should because your left side brake lights wouldn't work otherwise). Next test for power on the yellow wire when the brake pedal is pressed (again you should have power because this is the left side output wire). Finally, test for power on the dark green wire when the brake pedal is pressed. If the problem is with the T/S switch then you won't get power there - that's the right side output wire.

Thanks WhiteBird00, I will give that a shot this weekend... doesn't sound too hard.

Assuming it is the T/S switch, because no power via the dark green wire, what would need to be replaced? I see AutoZone carries a new turn signal switch for $30.99, I suppose that would be it?

Thanks WhiteBird00, I will give that a shot this weekend... doesn't sound too hard.

Assuming it is the T/S switch, because no power via the dark green wire, what would need to be replaced? I see AutoZone carries a new turn signal switch for $30.99, I suppose that would be it?
What you would need is the turn signal switch itself - not the lever that holds the wiper and cruise controls but the part that's inside the column under the steering wheel. I would be surprised if AutoZone carries it. The GM part number is 1995963 and it retails for about $61 at the dealer but is available online for about half that price.