Right brake light burns out

Hey all;
My brother has a 99 GMC Sonoma. Ever since he bought it, the right rear tail light keeps burning out. It's the light that's the turn signal and brake light all in one. He'll put it in and it'll burn out within the week. I'm going to check it out on Friday for bad grounds and faulty wiring, but is there anything I should look for or something I should know about? I've seen other trucks with the same problem. One of my friends has a late 90s S10 and has the same problem. Something I need to know??? Thanks guys.

I searched the forum and did not find any other complaints like yours. Seems odd. I've never had this problem. My factory lamps in my 96 blazer lasted 9 years.

When your brother replaces the lamps each time, does the new one work immediately? with no effort or jiggling?

Did he, or can he check with an OHM meter if the actual filament on the old lamps are actually open circuited? (broken filament)

Check the socket for signs of heating and / or corrosion. It does not take much corrosion to stop 12 volts. Corrosion can give the impression that a filament is gone. The act of pulling out the old lamp and inserting the new lamp can sometimes scrape away enough corrosion to get the lamps working again, temporarily.

You say it's been happening since he got it - as in - for 6 years?

No insult intended, but make sure your brother is using the correct lamp. Different lamps even though they may be auto type can be rated 12volt or 14 volt and have different hour ratings. 12 volt lamps burn out much faster than 14 volt lamps.

If he has been changing them constantly for 6 years, he may have lost track of the correct lamp.

Thanks for the reply.

I should've stated that he's had it for about 7 months now. He recently bought it from a dealer.

It works when he puts it in and then burns out about a week later. He's not a car guy, I'm his mechanic. I've seen the bulbs and they've been burned out each time. He has one left and I'm going to see if it's the right one tomorrow when I look at it. For some reason I'm thinking it may be the wrong bulb. I'll run to the store and see if he bought the right ones. Also going to check the wiring and clean the terminals and see if something there is wrong.

I'm going to check the circuit tomorrow and see what the deal is. I just find it weird that it keeps happening, but I think it's his fault. He doens't know what he's looking for ;-)

Check for wiring shorts.