2015 Sierra Denali 5.3 Eco Tech acting crazy

[Iridium Denali]

   2 - times when I came to a stop it went dead.   1- time it went dead with lane departure showing.   Every time when I crank it back up the voltage goes way up for a minute.

   Power steering hanging up when turning.

   3- times a very load bump noise coming from the passenger side dash or under hood.

   The moon roof will not open sometimes but clicks.  Then when it does open it wont close.  When these problems happen it works after a while.

   All these problems have taken place within the month.  My truck has 66,000 miles on it.

[Lsgun1]

I'd start there

[Grumpy Bear]

I had a Buick LaCrosse act like that. Traced it to a dead cell in a new battery from Walmart. A load test would show this and a local auto store or a Batteries Plus can do the test. System has a minimum voltage requirement to keep things working right. Before I had mine fixed it locked me out of the car once. No fun there when the keys are on the console.  

[JimCost2014]

This ^^^^, bad batteries and the new trucks are a very bad relationship.

 

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