What did you do to your NNBS GMT900 Tahoe/Yukon Today?

[Down8]

Replaced my 4WD switch, b/c I was getting intermittent Service 4WD errors. We'll see if this was the issue.

More cool: I installed a cheap-o Amazon Android 12 head unit.

Everything I've tested so far works. Most importantly is the Android Auto connection, which is automatic, and makes my wireless charger in the center console not useless when needing navigation.

-bZj

 

[Fubar0715]

I would let it sit overnight and check resting battery voltage in the morning at the battery terminals before 1st start.
I forget what the spec is but 12.4v I think is ok, any less than that may be questionable
and as for the rest ya low voltage causes all kinds of wierd things to happen

Thanks Wes - took your advice and let it sit overnight until about noon and 20' temps. The multimeter shows a grand total of 11.9 volts - it did start but was sluggish in doing so. I think the battery going to fail in the very near future and the cold exacerbates the issue. Time to go find my a new one!!!

 

[Doubeleive]

Thanks Wes - took your advice and let it sit overnight until about noon and 20' temps. The multimeter shows a grand total of 11.9 volts - it did start but was sluggish in doing so. I think the battery going to fail in the very near future and the cold exacerbates the issue. Time to go find my a new one!!!

yep that is a dead battery according to guidelines, usually happens due to weather change more than anything. Or if the battery got drained real bad that can kill even a new battery seems like they just never recover properly.

 

[Tonyrodz]

Replaced my 4WD switch, b/c I was getting intermittent Service 4WD errors. We'll see if this was the issue.

More cool: I installed a cheap-o Amazon Android 12 head unit.
View attachment 419437

Everything I've tested so far works. Most importantly is the Android Auto connection, which is automatic, and makes my wireless charger in the center console not useless when needing navigation.

-bZj

Which radio did you get? Have a link?

 

[mikez71]

Charged my ACDelco AGM batteries today. Both about a year old.
When I plugged in my old Schumacher charger (With AGM specific mode),
it showed 90% (main) and 95% (aux) for my batteries. (30 mins after a short drive)

The Schumacher gradually went up to 16.4V in about 1-2 mins for each battery!!!

I un-plugged each battery at that voltage fearing it would keep going up and damage the batteries (and explode in my face).
Plugging it back in, it would show 100% and not charge anymore.

Then I plugged in a Bettery Tender, which after a minute would also say fully charged.

Surface charge after 15 mins about 12.8V. (Usually shows 13.1V right after a drive)

Decided to do this because in the mornings, my battery voltage is around 12.3V.
Have heard the factory system only charges to 80%.

I did change a few ECM settings previously (HPTuners)
Alt DC min from 36% (12.45V) -> 58% (13.70V)
Diag min voltage trigger from 11.2V -> 12.2V
Diag boost voltage from 12.8V -> 13.5V
Settings show 600 seconds that diagnostic boost voltage can be requested,
but on newer chevys (2018) that setting is 14V for a max of 60 seconds.

Minimum charging voltage hasn't been below 13.5V.
After startup, it usually charges at 14.4 - 14.7V before droppping to 13.5 - 13.9V.
But morning batt voltages stayed more or less the same.. (*might* have changed from 12.2V to 12.3V after sitting overnight)

I am guessing the Delco's just rest at a lower voltage than what is shown online for AGM's.. and/or I have a parasitic loss..
No power issues yet, just wanted to check up on the batteries..

 

[89Suburban]

Which radio did you get? Have a link?

X2, I'm already liking the power/volume/tune buttons.

 

[Doubeleive]

Charged my ACDelco AGM batteries today. Both about a year old.
When I plugged in my old Schumacher charger (With AGM specific mode),
it showed 90% (main) and 95% (aux) for my batteries. (30 mins after a short drive)

The Schumacher gradually went up to 16.4V in about 1-2 mins for each battery!!!

I un-plugged each battery at that voltage fearing it would keep going up and damage the batteries (and explode in my face).
Plugging it back in, it would show 100% and not charge anymore.

Then I plugged in a Bettery Tender, which after a minute would also say fully charged.

Surface charge after 15 mins about 12.8V. (Usually shows 13.1V right after a drive)

Decided to do this because in the mornings, my battery voltage is around 12.3V.
Have heard the factory system only charges to 80%.

I did change a few ECM settings previously (HPTuners)
Alt DC min from 36% (12.45V) -> 58% (13.70V)
Diag min voltage trigger from 11.2V -> 12.2V
Diag boost voltage from 12.8V -> 13.5V
Settings show 600 seconds that diagnostic boost voltage can be requested,
but on newer chevys (2018) that setting is 14V for a max of 60 seconds.

Minimum charging voltage hasn't been below 13.5V.
After startup, it usually charges at 14.4 - 14.7V before droppping to 13.5 - 13.9V.
But morning batt voltages stayed more or less the same.. (*might* have changed from 12.2V to 12.3V after sitting overnight)

I am guessing the Delco's just rest at a lower voltage than what is shown online for AGM's.. and/or I have a parasitic loss..
No power issues yet, just wanted to check up on the batteries..

my 3yr old interstate agm's have a resting voltage of 12.2/12.3 which is a 70% state of charge (for AGM), I do have a 3rd party alarm and a somewhat asleep dashcam, a 4g hotspot and ipod always charging which do not add much drain, should be very neglible
my charging system currently works well
the problems with agm's (that I have experienced) is when they start not holding a charge, they will show charged but are not charging when when warmed up or do not allow the rvc to operate properly, resulting in rvc mode malfunction and low state of charge, they basically refuse to charge or show charged but will be in a low state in a short time period.

 

[Fubar0715]

Reading of the shortcomings of AGM batteries - are members recommending using them or sticking with traditional flooded batteries? In my case, all stock with nothing drawing when not in use - extreme cold for a few months a year.

 

[mikez71]

my 3yr old interstate agm's have a resting voltage of 12.2/12.3 which is a 70% state of charge (for AGM), I do have a 3rd party alarm and a somewhat asleep dashcam, a 4g hotspot and ipod always charging which do not add much drain, should be very neglible
my charging system currently works well
the problems with agm's (that I have experienced) is when they start not holding a charge, they will show charged but are not charging when when warmed up or do not allow the rvc to operate properly, resulting in rvc mode malfunction and low state of charge, they basically refuse to charge or show charged but will be in a low state in a short time period.

Noticed some desulfation processes can bump the voltage up near 18v!
Perhaps the Schumacher was trying something there...

Just remembered I had unplugged the RVC a couple days earlier to see if the charging voltages would be any different.
Haven't really noticed a difference, at least when compared to the modified charging settings..

 

[mikez71]

Reading of the shortcomings of AGM batteries - are members recommending using them or sticking with traditional flooded batteries? In my case, all stock with nothing drawing when not in use - extreme cold for a few months a year.

Have heard they are supposed to be better in cold and more sensitive to heat.. I'm in the heat myself but thought I'd give them a try anyways.

 

[mikez71]

X2, I'm already liking the power/volume/tune buttons.

Nothing beats dials!

Why I want to install manual climate control..

 

[89Suburban]

Nothing beats dials!

Why I want to install manual climate control..

Me too!!! Let me know if you make any progress on that please.

 

[mikez71]

Me too!!! Let me know if you make any progress on that please.

Definately will do. I have the wiring printed out and had made a note of which wires to repin, but haven't gotten back to it.
Thinking I might work up the courage after my headgasket/motor mounts which I've been dragging my feet on..

 

[Rocket Man]

I uisually always have around 15 gallons of propane and the same in gas for the Generator, last thing I need is a freezer full of food going bad. Other than rain and some freezing last week it hasn't been bad here better than I expected. It's been hitting the higher altitudes.

Yeah I’m not feedin a small army like you are. If I was ever to lose it long enough for food to go bad,, it would be about fifty bucks worth between my freezer and fridge. But I have never been without power for more than a few hours, power company dude said I’m on a great feeder line. Everything is back to normal again today, put away the ice shoes.

 

[Rocket Man]

Reading of the shortcomings of AGM batteries - are members recommending using them or sticking with traditional flooded batteries? In my case, all stock with nothing drawing when not in use - extreme cold for a few months a year.

I have Interstate AGM’s and haven’t had an issue in the cold although last week when it was 15* for a few days I noticed my 02 struggled to turn over. I plugged in the block heater and the next day it started right up so I’m guessing it was just the extra effort to turn over the old iron when it’s that cold.

 

[Doubeleive]

Reading of the shortcomings of AGM batteries - are members recommending using them or sticking with traditional flooded batteries? In my case, all stock with nothing drawing when not in use - extreme cold for a few months a year.

I started using agm's almost 20 years ago because I got tired of traditional battery's just going dead out of the blue, my experience has been the agm will atleast give you a running chance to replace it before it dies. I have never had one just flat out die, more of a slow death.
These Interstates are maybe on there last year not sure first time I have bought them always ran Die hard when they were made by odyssey for sears, then they changed brand and I ran the branded odyssey's until it seems like they barely make it until the 3yr warranty expires anymore. last one I tried to warranty would say it was charged but it was barely within spec at best and they denied the warranty so I said screw it and switched to the interstate's which should be real close to 4 years now I think i bought them in may/june 2020 bought the same battery for the silverado in feb 20 (which is fine also) and these ones right after that.
found my post from 2020

What did you do to your NNBS GMT900 Tahoe/Yukon Today?

TruCool 40k hands down. It’s been the consensus among pretty much everyone for quite awhile. There’s lots of write-ups on it too, google it. Thanks.

www.tahoeyukonforum.com

 

[gooffeyguy]

I've had an H6 AGM in the 2012 since June of last year and it didn't even hesitate during this below 0 temps we were having all last week, even when sitting for 2-3 days before being started.

I just bought the same H6 AGM battery for the wife's Acadia and installed it this past Wednesday. Her ACDelco Gold battery dated March of 2020 (which only has a 30 month warranty) gave up the ghost the weekend before and wouldn't start in the cold. I was able to get it to start after putting a charger on it, but even after driving it around that day it was dead the next morning after sitting overnight in the cold.

The H6 AGM's I got have a 4 year warranty

Here's the weird thing, everyplace I looked online for her battery it said that an AGM was spec for her car, but the battery that was in it wasn't an AGM. The non-AGM battery was only $20 cheaper.

Also, that H6 size (group 48) is a very popular size and it took a lot of phone calls to find a store that had them in stock, even though it would show in stock online but after getting there they weren't.

 

[Fubar0715]

Thanks everyone - Going with an AGM replacement and probably the Interstates from Costco.

 

[gooffeyguy]

Thanks everyone - Going with an AGM replacement and probably the Interstates from Costco.

The Interstate H6 AGM at the Costco around here are $169 and have a 3 year warranty. They were out of them.

I ended up getting the Everstart Platinum AGM from Walmart for $179. It has a 4 year warranty.

I have about 6 Walmarts within 10-15 miles of me but only 2 Costcos, so it was easier to find one in stock at a Walmart.

 

[Geotrash]

Looks like my 4-year-old AGM in my 2007 is starting to talk to me. When I start it in the AM when it's cold, the climate control has started defaulting to 74º on both sides, and 'Auto' is turned off. Best guess is that the battery voltage is dropping overnight. Gonna get a volt meter on it tomorrow to find out for sure.