Had a connection on the board of a credit union and got hooked up and bought a repoed 2009 GMC Yukon 118k miles.
Ended up buying it for $2500, basically non-running and had been sitting for 7 months. Here's what's happened so far:
- replaced two driver side doors as it was involved in a malicious collision, owners boyfriend ran into the side
- took to gm dealer to clear codes, needed new hybrid control module
- still at dealer recharging individual cells to get to "jump assist" mode, needs to be at 240v to enable that mode.

Anybody know anything about this "jump-assist"? I can't find ANYTHING on it.

I'm hoping the batteries aren't shot after sitting for 7 months.

 

99.99% certainty the battery is toast.

You can't leave a nearly 10 year old, 100K+ NiMH hybrid battery sitting for months and expect it to survive.

Jump-assist sounds like a bunch of hooey, but Hillbilly might chime in and shed some light.

The requirement isn't exactly 240V. The requirement is actually that all 20 blocks be at 12V or higher. The ~50A spike or so needed to spin and fire the ICE will zap a depleted cell. A block at 12V is actually depleted, but there's likely enough voltage depressed capacity that they'll survive a start with only slight damage.

You should just plan on replacing the pack with a new one. All your other options are lower value.

Good luck.

 

That was good info- thanks S. dealer called and said battery needs to be replaced, problem is their price is $1200 more than what I saw online genuine gm part. I called a local hybrid repair shop and they said they can do a rebuild of the batteries. Anyone have any experience with that? I'm ok with getting the new battery pack, just wanted to look at the options. If I was able to purchase the battery from a third party this repair place could also install but I'm not sure they could finish the job without the gm dealer scan tool.

 

Online prices are irrelevant. No online source will sell you a battery. The only source for a new hybrid battery is the local dealership from which you purchase it. OTD costs are about $3500-3800. Read some of the recent threads on this site. Many discussions of replacement options.


If you pursue a rebuild of the battery, you will be throwing money down the toilet. You will be dealing with the battery issue again in the short term. The GM hybrids have demonstrated a tendency to damage their batteries to the point that reconditioning/repair is not viable. This is also true of the Generation 3 Toyota hybrids (same battery manufacturer).


If you want to fix the problem, new battery. If you want to take extreme risk with a high likelihood of only a short-term fix, then go with not-new.


Good luck,


Steve

 

Thanks S. already pulled the trigger on the new battery this morning. I think that was the best way to get the most life out of the car. Excited to finally get this thing going. Little hacked that we spent the cash on the control module when the battery needed to be replaced to run, shouldn't the dealer have run tests on the battery first?

 

Glad to hear it. It's definitely the long-term fix. I can't comment on the control module or method of diagnostics. With so many interrelated systems, diagnosis is frequently difficult for anyone below "expert," and there are too few GM hybrids for there to be a lot of experts wandering about.

 

GM has a huge problem blaming everything BUT the battery.

 

Wait until the even MORE complex self driving car fleets begin to age!