Car won't start, disconnect battery for 10 secs and its starts. Need help!

[Bliggity]

I recently purchased my wife an 08 LT 2WD 5.3 Tahoe with 84k. We have owned it for a few months and it's acted up on us three times.

Three separate and random times the truck will not start. We will go out to drive it somewhere and there will be no interior lights, no cluster lights, nothing at all, cannot lock or unlock doors with fob, etc. Engine does not crank. Nothing happens at all. The locks on both front doors sound very "glitchy". If I disconnect the battery for 10 secs or more the truck starts fine with no hesitation. And the truck will be normal like nothing has happened for a few weeks. The first time this happened I tried to jumpstart but no luck, only after I disconnected the battery did it fire.

I have taken the battery to a parts store and had a master tech check the battery and it shows no issue and doesn't even need a charge. The battery is only 1 1/2 years old. Also, the alternator has been charging normally too (sounds like the bearing may be getting louder).

I am wondering if the body module or something else is disconnecting the battery from the car for some reason and until I disconnect battery then reconnect it resets or clears whatever is occurring.

 

[Ponchonutty]

Could be but I would suspect the battery cables being bad. Common issue. Another issue can be the fusebox under the hood too.

 

[Physh1]

Sounds like you've got a bad/intermittent connection somewhere or a dirty battery connection. Double check everything...

Cameron

 

[NathanJax]

Could be but I would suspect the battery cables being bad. Common issue.

x2

 

[Bliggity]

I checked the connections at the battery, and the majority of the positive and negative cable connections/grounds. I did put a large load on the car and the volts dropped to 12.3. I also did notice on one occasion the negative battery cable about a foot of it closest to the battery was very hot when my no start issue was happening.

 

[Ponchonutty]

OK, if you have a cable that is hot, you have a short inside that cable. Buy a new ground battery cable and see if that helps.

 

[mike1944]

Could be but I would suspect the battery cables being bad. Common issue. Another issue can be the fusebox under the hood too.

x3. Even a tiny bit of voltage fluctuation will make the computers do strange and frightening things. Be sure the connections are clean and tight.