In December I noticed the headlights, tail lights, and interior dome lights on my Tahoe were occasionally flickering, almost more like pulsating. I would be driving down the highway and they would start flickering but would eventually stop. The guage sits either at 14 or just above it no matter if they are flickering or not. Well now they are flickering constantly and it's driving me crazy! The nav screen will flicker occasionally as well, but not to the degree of the lights. Is this an alternator problem or something else? The battery is less than a year old btw.

Any help would be much appreciated, thanks!

 

Welcome to the forum.

Could be a loose ground connection.

 

Thanks for the reply. Sorry if this is a dumb question, I am not very knowledgeable about the electrical system. Where is the ground connection that I should check?

 

Another thing I noticed tonight is that the lights flicker when at idle but if I shut off the engine and leave the lights on they are steady, no flickering.
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Not sure if that means anything or not, just thought I would throw it out there.

 

I have seen something similar with my 04 Burb and verified the primary ground is good.

Did you ever figure this issue out with your Tahoe?

 

Check the connections at the battery and at the alternator. What is the reading on the battery gauge?

 

Cab voltage meter looks to be about 13.5 or so. Using a regular hand meter it is 12.4 with the truck off and 14 when it is running.

 

@ sbrenton - I have not figured out the cause as of yet. Today one of the low beam bulbs burned out and they are less than a year old too, and a pain to install to boot! So something is not right for sure...
I have checked all the grounds that I could locate as well as the battery and alternator connections and all seems good. I am going to take it to the dealer next week and see what they say. I will report back after that (fingers crossed)!

 

Mine reads about the same as sbrenton's when vehicle is off and on. While driving the meter might be at 12.5 or so one day to above 14 on another, is that normal?

 

An update: I replaced the burned out low beam on drivers side Friday evening and started it to run an errand. I replaced the other side bulb on Saturday am. When I was finished I went to start the car and the battery was totally dead, jumped it and took it to the parts store for a quick check and they said that the battery and alternator were both working fine, I probably had the engine running for about 30 minutes. On Sunday morning the battery was again totally dead, doors wouldn't unlock with remote and lights didn't come on, I jumped it again and drove it for about an hour and it has now started every time since then and to top it all off, there has been ZERO flickering light issues!

So, what happened? The battery dies overnight twice after replacing low beam lights and now everything seems to be working just fine. Were the old low beam bulbs somehow causing the flickering lights? Why did the battery just die overnight and now runs fine? I am stumped for sure. I had an appointment with the dealer tomorrow and I guess I will still take it over there and see what they say.