2006 GMC Sierra not starting, not clicking, and absolutely no interior lighting.

[Rin Suggs]

I have a 2006 GMC Sierra pickup that I had the engine totally replaced (as well as most of the front end) on about month shy of 2 years ago. About a month ago, I went out to start it up, as it's my main mode of transportation, and the key fob wasn't working. I manually got it open and realized my interior lights weren't coming on. I tried starting it and it didn't do anything, not even the normal rapid -click click click- of the battery being dead. I still didn't think anything of it, and had my aunt take the battery up for testing and charging at the auto parts store. They said it was completely dead, charged it, and told us that it's reading "good battery".  We put it back in the truck, the key fob started working, the interior lights were on, and I figured "yep, alrighty, we got ourselves a battery issue". My aunt put the key in to turn it on, and as soon as the key turned, everything shut down all at once. Once again, no interior lights, no clicking, absolutely no response whatsoever. The little battery output gauge we have in the phone charging port was also reading 6.7 suddenly (if that last part matters at all).

I've had 4 different people tell me 5 different things, and I just can't afford to try all these different options right now. With my truck being down, I've been relying on rides from people and missing out on a lot of work. I just need a solid idea. I'm at my wit's end here and have no choice but to try to figure this out.

Thank you guys so much in advance. Any advice helps.

[diyer2]

Start with a new battery.

[txab]

^^^^For sure! Then have the charging system tested. Check battery cables for integrity. You can have them go bad internally and not notice it

[Jsdirt]

6.7V ain't gonna cut it! 

 

BUT ... unless you test directly at the battery, you can't be 100% sure the battery is smoked. The symptoms you described after attempting to start are a classic bad connection at the terminal symptom. The battery still could be toast, but I'd check the terminals first. 

 

Before even removing them, give them a wiggle and try to crank it again - if it cranks and/or starts, that's your issue.

 

Remove the terminals from the battery, sand down the posts and terminals, and re-connect. Make sure everything is TIGHT and can't be wiggled. If it fires right up, or cranks and immediately quits again with low voltage and no interior lights, then you've got a connection problem still that needs to be investigated. You might need new cables.

 

If you've got those crappy clamp-on terminals, I'd bet on it.

Edited January 4, 2025 by Jsdirt

[Rin Suggs]

12 hours ago, Jsdirt said:

6.7V ain't gonna cut it! 

 

BUT ... unless you test directly at the battery, you can't be 100% sure the battery is smoked. The symptoms you described after attempting to start are a classic bad connection at the terminal symptom. The battery still could be toast, but I'd check the terminals first. 

 

Before even removing them, give them a wiggle and try to crank it again - if it cranks and/or starts, that's your issue.

 

Remove the terminals from the battery, sand down the posts and terminals, and re-connect. Make sure everything is TIGHT and can't be wiggled. If it fires right up, or cranks and immediately quits again with low voltage and no interior lights, then you've got a connection problem still that needs to be investigated. You might need new cables.

 

If you've got those crappy clamp-on terminals, I'd bet on it.

My aunt and I tag teamed this. I check the terminal and it was loose (I have no idea how I didn't notice this before). She wiggled the terminal and I noticed the interior lights come on. So I tried turning it and it clicked. So I tried again and it started right up like it was nothing. The battery output was great and it sounded perfect. Going to go with the rest of your advice. I can't thank you enough for helping me identify the problem!!!