you could have a weak battery,? Have a load check done on the battery, its easy to do, most parts houses do this free of charge.

Otherwise you have a power drain somewhere in the car? It draws it dead over night. I would unhook the neg side when you shut it off at night and then re connect it in the morning , and see if it starts then?
Then you would know if there is a drain somewhere.
Good luck.

 

These use a LANBUS system to control just about everything. So if the computer is not receiving enough power then you will have all kinds of weird thing going on.

You may have a power drain issue going on as well. Make sure your vehicle is up to date with all necessary computer updates from GM. I seem to think power drains happened with the some 09's but they had a fix.

The battery is a good starting point though as it 4 to 5 years old now depending on you build date.

 

The battery on my 2007 Trailblazer SS was replaced under warranty before the 3 year / 36K mile warranty was up... So it could easily be the battery... even if only 4 - 5 years old...

 

I would agree, start with the battery. You are lucky if you get 4-5 years out of one that comes new with a car nowadays, especially with the load that newer vehicles draw. I would would change it away, since winter is fast approaching.

If it doesn't drain the new battery, then you know you;re good. If it does, then something else at play here. Do you have the Navigation? There was a problem with those that had the Nav system, and the battery being drained, although that problem would most likely have come up by now.

 

There were 3 main reasons with the earlier models why the battery would drain unexpectedly from what I remember. The instrument panel was not going to "sleep" and allowed some items to remain on and drain the battery. I don't recall if the IP had to be replaced or if a software update remedied it.

The navigation unit would drain the battery. A software update needed to be done to correct this.

The back up sensors would not shut off if the driver did not go into Park and let the car run for a few extra seconds. There would be no sound letting you know they were not shut off, just a dead battery the next day. Again, I believe a software update took care of this one also.

These items were all resolved by the 2010 or 2011 models if not even earlier.

I agree that your problem is probable the battery itself. There are many auto parts stores (Auto Zone, etc) that will do a free battery and alternator check for you.

 

Thanks everyone for the replies. I bought a new battery today and will install it tomorrow. Hopefully that cures the problem. I will let everyone know if it does or does not.

Murnutz

 

I would of had them run a load test on the old one , just for the heck of it , then youd know

 

Re: Weird Electrical Issue - Update

Okay everyone so I have an update to the post. The culprit was something easy to fix...a loose positive cable on the battery. I did go ahead and put the new battery in the vehicle though. I'm military and have to go deploy next year for 365 days and figured it was better to replace it so my wife doesn't have to worry about it while I'm gone. If someone has a similar problem like mine I would first check the battery connections.

Thanks for everyone's advice and input. Have a good one.

Murnutz

 

Good job thinking ahead for your wife and thank you for all you do for us

 

Thanks for the feedback, something to remember as electrical connections get older and something that is free to check first. A big thank you for your service to our country and my very best to you and your wife while you are separated, it can be a tough time. :thumb: