Hi evois,

Yes it starts up just fine. The problem only occurs randomly when I come to a stop, and then start going again, when it switches from auto stop to engine

 

There should be other codes besides the battery. Mine showed the battery code and the fuel pump code. The dealer replaced the battery only to find out that the hybrid would not start. It was the fuel pump all along. Have them check all the other codes and fix them first before doing the expensive battery.

 

The Snap Shot data should help greatly to confirm his diagnosis. Especially if he can get one on a stall. A battery with damaged chemestry will heat up hotter faster.

The HV battery should be not much more than $2500 with exchange of old one as a core. Then labor.

 

Yeah they quoted me a total of $4250 with labor.

All the codes pulled were
P0AC4
P0BBD
P061B
U0073 < they weren't sure why this AC code was popping

 

There's a place locally called the hybrid shop (part of a national chain) who said they could diagnose for $67 and give me a second opinion. They claim the dealership is too quick to just say "it needs a new battery". So they want to diagnose it more thoroughly.

They also said if it is in fact the battery, they can recondition it for under $3000, and they have had many happy customers doing so. Not sure about this route yet though

 

Something that just clicked in my brain... that AC related code U0073 that the tech wasn't sure why it was stored. The AC in the hybrid is electronically driven by the hybrid batteries, it would make sense that while in autostop, and the AC running it is putting a large load on the batteries, and maybe if the battery is not running optimally it is drawing it down enough so that cranking the engine back on when I start going again just isn't happening? It would make sense, seeing as how I t only stalls on hot days, when the AC is on, when the car goes from autostop to crank the engine.

I also came across this bulletin, which the tech didn't mention. its related to my model, and also the code, and the intermittent cranking issue Im having:

http://engine-codes.com/uploads/gmc/08-07-30-021E.pdf

Any thoughts on this bulletin?

 

You should be able to get a NEW battery for under $3000. How about $2000?

https://www.parts.com/index.cfm?fuse...calade-BATTERY

 

That would be nice, unfortunately I already called all the GM parts distributors where you can find good deals like that (GMParts east, GMParts direct etc). And although they list the batteries for such a great deal, everyone said you can't actually buy them from them anymore, I have to order through dealership. Never ran into that buying parts, I always order from GMParts direct

 

Just got the truck back from The Hybrid Shop out in Virginia beach. They said the HV battery is fine, and there's no need to replace or recondition it. They said my issue was with the transmission somewhere but they are not able to work on transmissions so they can't help me any further, or diagnose the transmission.... Dang.

They showed me GM bulletin PIT4808D which pertains directly to my problem, codes etc. it basically says if it's an 08 Tahoe stalling with any of these codes: P061B P00BBD P0AFA (I have two of the three) that the tech needs to call the technical assistance center.... No further information