I have a 2007 Chevy Tahoe LTZ, and I am having a problem with the passenger side lowbeam headlight. The bulb has burned out 3 times in the last 6 months. I replaced it yesterday (3rd time), and as of this evening it is out again. I changed the alternator to a 160 amp version about 8 months ago, so it kind of lines up with when the problem started. I did a voltage test on the battery this evening and I was getting a pretty consistent 15.86 at 1500 rpms. Everything I’m reading tells me that the voltage is too high, but that my reader may be off by a volt or 2, and it is strange that both headlights don’t have the same problem (assuming it’s a voltage problem). Yesterday when I changed the bulb, I also replaced both terminal connectors that connect to the bulb. I used gloves when changing the bulb, and there is no condensation that I can see. The bulb also seems tight, so there shouldn’t be any abnormal vibration. The headlights are after market, and have been on the vehicle now for roughly 3 years. Does anybody have any insight to share on this? Thanks in advance!

 

Change the complete socket for the bulb and use dielectric grease on the bulb and hopefully that will work.

 

Bad bulb connectors are a issue across the gm lines. I clean the bulbs with alcohol before installing and use the alcohol soaked paper towel to handle them. Gloves could still have something on them. If your using Silverstar bulbs they burn out quickly.

 

Thanks. When I installed the aftermarket headlights i used quick splice connectors. Could that have anything to do with it?

And in the event that I was dealing with a voltage issue (bad alternator), wouldn’t both headlights be affected and not just the one?

 

If the splices are not a good ones then it could cause your problem. A bad alternator would cause other electrical problems as well.

 

I want to thank you for all of your help. I took it into the local auto parts store and had them test the alternator. Apparently the voltage regulator is bad. I am going to replace the alternator, replace the bulb socket as you recommended, and I will give an update in a couple weeks for anybody who comes across this thread who is having the same issue. Thanks again.

 

yeah 15.9V seemed to high to me.

I've never heard of a meter being a whole volt or two out. If it is then it needs to be thrown away.