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.