A 5 year old 12V is always suspect. Unless you've applied a load test to it, it's hard to conclude that it's ok.

Given the lack of the typical battery failure codes, you need to conduct a discharge test The battery related code MAY indicate a failure.

Tahoe_08's recommendation of "replace the offending cell(s)" is magical thinking. It's been well documented that once these batteries show signs of failure, the damage is widespread and devastating. Detailed testing has shown that almost all of the modules are at less than 20% rated capacity with maybe 1-2 "usable" modules (something above 50%).

Instructions for discharge test:

https://www.greenhybrid.com/forums/f...36/index2.html

In depth pack analysis with testing of all 40 modules:

https://www.greenhybrid.com/forums/f...ry-pack-31796/

 

Yes yes and yes. Judging by your later posts too I'd still say it's the hybrid battery. I had a similar High Voltage code too. Please just replace your battery and go from there. GreenBeanBattery does a 6 month finance thing, so it's $500/mo interest free if money is a concern. That's what I did anyways. If they didn't test the batteries under load and only idling then they didn't get a good readout. These packs will test fine on idle but the second they go under load the readouts will be all over the place. The aux pump is going to give you transmission codes and you have none. If the fluid is clear and smells nice I'd be willing to bet that's not an issue. These transmissions are bulletproof, i've only ever seen one post here of one that busted at 180k (and hhe was driving it in Arizona summer at about 100mph regularly) I have a 2009 as well that had issues at 92k - obviously higher than 70k but I was throwing codes then as well - and battery age / if it's been sitting for awhile does factor into the health of the battery.

I obviously can't give you a 100% blessing of positivity but from the symptoms you describe and the age of the truck, I'm fairly confident that it's going to be your battery. It feels EXACTLY like transmission issues. I was about to replace the aux pump myself too until I saw the hybrid battery codes.

Also the high oil pressure, if it's the oil sending unit screen, is like a $5 fix, or if you take it to the shop, $100.

I don't quite have the knowledge that some of these people do with battery testing, but if you're anything like me, not retired, don't have a ton of money or time to work with, it really is worth it to just get a new battery. The hybrid shop in LA i took my truck too also told me they didn't think the battery was bad and what do you know, it threw battery codes.

 

Hey Erik

Is your truck 100% free of that shudder/jerk jumping issue?

What else has improved with reconditioned battery?

You getting better gas Milage too?

Thanks Keith and Tahoe08 for input too. Much appreciated all.

When my tahoe runs without issue - it’s the best ride ever - like an electric dragon - fast, quiet and fun.
But the issues make it not fun on days where the truck is jumping at stop signs. My wife won’t drive it.

 

yeah mine showed signs of failure in May shuddering and jerking (they lied about the condition so they would not have to replace it. as it would have been a free replacement)( when it was summer it did not have that issue )and was dead by September it only sat for 2 days and bam dead battery with only 8 volts(we had a cold spell it had dropped 30F at night two day sin a row)

by October the hybrid stalled out upon an AutoStop Resume ...



it has another previous stall out on a exit ramp as well I lost all 12 volt power for about 2 seconds when the engine was running
i was going 55MPH as all the Brakes locked up it nearly caused a wreak with 2 other cars luckily they were paying attention....


between May and OCT
2 stall outs
6 engine run away (upon an AutoStop Resume) it just went straight to 6,000 RPM upon resume..
P0069/P0420/P0430/P0AC4/P061B/U180F /P0C32






so I bought an AGM battery at Walmart for $164 with 5 years replacement while Autozone wanted 169.99 for a old fashion flooded battery... with 3 years warranty replacement I even told them why i was not buying from them....


I'm still getting P0069 as pending but I highly suspect the ground connections since it is seen less after cleaning up the ground connections it need a more DEEP cleaning ... as i don't have a socket set to take them off i did use a heavy duty solvent and it helped a bit..

also by the way they use the exact same brand as Autozone Jonson Controls..


I plan to add a second dedicated battery to the Aux transmission pump


possibly even adding a 160amp alternator to charge the second battery

 

My shuddering is 100% fixed. Again, the 300v battery is tied to the transmission so it's part of the reason that my truck was shuddering and stalling on accelerations / switching from autostop. I have had zero issues with my truck since I replaced the battery. Put about 12k on it since the battery was replaced. Battery is under 5 year warranty unlimited miles so if anything happens I'll just get it replaced. You can look in my post history, I posted in a lot of threads about how I thought my shuddering was caused by this or that.... the problems that I was having were all entirely tied to the hybrid battery system. I did get a low oil pressure CEL once, but that was due to the oil sending unit screen getting clogged with ****. Very quick fix.

My gas mileage is about 18.9 right now. I do a pretty even mix of highway and city driving. It definitely helps for LA traffic. I also have the Range Technology AFM delete that goes into the OBD2 reader that disables the cylinder deactivation so it's always running in V8 mode, which likely takes off some MPGs but I'd rather prioritize preserving the lifters so they don't stick over having higher gas mileage. I also took the front unpainted air dam off of my vehicle (the one that this thread was originally referring to actually haha) so that I could have more clearance and I believe that may have shaved off a very small amount of gas mileage as well. I'm happy with it at 19. I know some people average 21-22 though. I didn't buy the truck for gas mileage, that's just an added bonus. Added bonus that cost me the price of a hybrid battery two months after buying it hahah. Zero problems thus far though, love this truck so much.

 

the Transmission Aux pump is tied to the 12volt system it's a 3phase 12VAC pump

AUXILIARY FLUID PUMP
The Auxiliary Fluid Pump is a 3 Phase 12 Volt AC motor type that is turned on by the Auxiliary Fluid Pump Control Module (AFPCM) when the vehicle comes to a stop and the engine is off. It provides lubrication and keeps the Hybrid Low-1-2 Clutch applied in preparation for initial take off.
it's more then likely it's ran off the 12volt DC doubt the would have another hidden 300vAC 3 phase to 12volt 3phase step down transformer..
as you can run a 3phase motor off of DC very cheaply rather then add another HIGH power cable or step down




there also a TSB for the transmission aux pump 2008-13
https://static.nhtsa.gov/odi/tsbs/2016/MC-10083106-5448.pdf
https://testing-public.carmd.com/Tsb...112362/4364020
https://static.nhtsa.gov/odi/tsbs/2016/SB-10095613-2280.pdf
https://static.nhtsa.gov/odi/tsbs/20...63441-2273.pdf

Those are terrible numbers MPG wise .. i'm hitting upward of 31MPG in the city 28.7mpg combined 26.7MPG on the highway on a 11 years old battery used up battery.....


looks like there could be a wire fault or "wire rubbing"



The secret is to manipulate the engine to run lean or in V4-DFCO.... I going to do some Aero mods to see if I can get it to 40MPG.
i'm just waiting to settle with the Surety bond first

( as the dealership lied , this hybrid was in a moderate accident with airbag deployment) the carpet was cut up where the airbag module was, they claimed it was never in an accident...

i'm probably going to get about $6-7,000 back


i'm not going to lie my worst city mpg 12.8MPG i was running it in Manual mode because we had snow, Engine BRAKING is much better in the snow as it keeps the wheels turning, friction brakes are the worst in Snow/icey conditions as they can easily lock up and you just spin out ... with the engine braking i could come to a complete stop with just the Regeneration/Engine braking in the snow it was pretty snappy as well almost as fast as using the friction brakes

 

Tahoe08 my 12v car battery is exactly 4 years old and while
I drive the battery readout is usually between 14-15 volts - and when it dips
down to 13 volts the truck still
runs fine.

When ever the random (dangerous) shuddering - jerking issues start - it doesn’t seem to relate to the voltage on my 12v battery because I watch the battery VOLTS display while I drive and it often shudders even showing 15 volts.

Of course im tempted to only pay $200 for a new battery and have that fix the issue - but I would gamble
and believe Erik is correct that perhaps my hybrid battery is at the end of its useful life and is now causing problems even though it doesn’t throw codes


my other concern is - that my truck is acting up and having these dangerous drivability issues but NO related codes.

So if the GREENBEAN battery goes bad premature (cause it’s a rebuild) then they won’t honor the warranty because there won’t be related codes showing failure because I’m not getting battery codes even now - right ?

 

check the grounds mine showed 13-15 volts and still did it.


have it load tested with a Battery toaster tester

those chessey electronic testers don't work good...



I replaced the battery issue solved the battery was from March 2014. 100% Dead November 2019 .. it dropped under 11volts once the engine resumed we can say that was


The Inverter is not always supplying power the moment the engine starts is when the voltage drops enough that the AUX tras loses pressure (as the 12v+ will sag to 11-12v) " then catches up" when the engine is started as the main pump has power.. "that is auto stop lag"


another issue could be the AUX filter has never been replaced (it has two of them for the main pump and aux pump) this can require more current draw from the electrical motor if it is clogged



upon engine start it requires at lest 150-200 amps 12v+ current est ...plus what ever is being used..
while your driving this will drain the battery quickly and cycles them hard.




i think a good mod would be tricking the computer to keep the12v+ inverter on the whole time...



I might even add a

Ultracapacitor parallel with the battery for Maximum POWER this way there can be plenty of available current...

or a second battery

I did have one auto stop lag last night but i had a bunch of restarts while in traffic.... 10 resumes in a very short amount of time(in 5 min) it worked fine after it charged up driving 60miles home that day i had a total of 30 stops. 1 of 30 is better then almost every single time, like it used to happen
1 of several hundred since replacement of the battery


the first things I would look at are the battery and ground wires like i said it has 6 FAIL points

and if it's as crusty as mine you will have an issue you can see the wire is also damage...

that is 2 of 6 connects you can see how badly damaged they are the other 4 connections are just as bad


the one that comes from the inverter is 0 gauge and the other is 8 gauge from the firewall to the engine block to the battery... with the damage it's probably a 10gauge..
that one below is behind the inverter be careful it contains high voltage..






this one connects from the firewall to the engine block

 

31 MPG city in a Tahoe Hybrid?

Funny guy... 🙄

 

I was averaging 27mpg on the highway tell this hot weather rolled in, barely 23mpg (highway) getting into the 110s got that A/C running FULL blast(front an rear)