Volt Meter drops below 14 on a new Tahoe

[Vortex]

I bought my new Tahoe (2020) a few months ago and today I had to make a 300 mile trip down the interstate. I never really paid attention before but it always seemed to me it was indicating 14 (straight up) but Im sure it moved some. Today I noticed it was move between the straight up position and what I guess would be around 11, it did this several times and I was so paranoid about going dead I didnt even stop for a nature break. If you own a 15 or newer do you ever see your amp meter dropping from te 14 (straight up) to about the 10 or 11 as you go down the highway? It could be its totally normal and I never noticed it but it sure seems odd.

 

[Rdr854]

Yes, I have seen that on my 16, 17 and 19 Suburbans. Asked the dealer and they said it was normal. Never had a problem.

 

[Miami-Dade]

Same thing on my 16 Tahoe. Been doing that for the past 90K miles. Did it with the original battery and now with the newer AC Delco battery I put in a few months ago.

 

[Vortex]

Thanks guys, I appreciate it. Ive just never seen that on any car, I had a 2017 Tahoe and if it did it I never noticed. Guess I will just keep on truckin and if it craps out or battery goes dead the dealer can fix it.

 

[PG01]

Sighhhhhhh, discussed ad nauseam on here... since at least nbs models gm has been using an a system called rvc which shuts down the alternator when battery is sufficiently charged to save gas....

 

[Fless]

Your trucks have ammeters in the cluster?

 

[PG01]

Your trucks have ammeters in the cluster?

Lol

 

[Doubeleive]

Your trucks have ammeters in the cluster?

yes in deedy

 

[hcvone]

Usually around 14, but sometimes drops under that, installing dual batteries, one doesn't cut it in upstate NY, just too cold in the winter

 

[drakon543]

at 14v the alternator is running the truck and charging the battery at the same time. the alternator alone is capable of running the truck so if you drive long enough and your not using alot of the electronics the battery will be fully charged so the draw from the alternator will decrease. when you first start a vehicle the alternator is trying to recoop the slight drop from it sitting overnight and the juice you used to start the vehicle. also most charging systems have plenty to run everything in the vehicle charge a battery plus a little extra. so if you jump start a vehicle the gauge should climb above the "normal" position you see it in.

 

[Vortex]

Thanks so much guys. Im really happy with my Tahoe too, this is why I joined this forum, to answer any questions I have and I appreciate it.

 

[swathdiver]

I bought my new Tahoe (2020) a few months ago and today I had to make a 300 mile trip down the interstate. I never really paid attention before but it always seemed to me it was indicating 14 (straight up) but Im sure it moved some. Today I noticed it was move between the straight up position and what I guess would be around 11, it did this several times and I was so paranoid about going dead I didnt even stop for a nature break. If you own a 15 or newer do you ever see your amp meter dropping from te 14 (straight up) to about the 10 or 11 as you go down the highway? It could be its totally normal and I never noticed it but it sure seems odd.

There are detailed explanations on how this system works in the shop manual and the GM Upfitter's manuals. Look up the key words EPM (Electric Power Management) and RVC (Regulated Voltage Control).

For those of you with radio controlled cars, planes, boats, etc. this is basically a smart charger built into your truck, pretty cool.

 

[iamdub]

Yup- cool system, indeed.

It's to extend the life of the alternator and battery. A full battery doesn't need to be charged and an alternator doesn't need to be loaded down charging a full battery. Also, a battery needs to be cycled, so you'll see it being discharged and charged on a long trip.

 

[TheAutumnWind]

my gmt400 with an overdriven ad244 upgrade even does it. I never see it below 13 or so though. I'm sure its a more rudimentary deal than whats on the newer trucks, but it has a signal wire that reads battery/system voltage and varies the load on the alt.

 

[wjburken]

Your trucks have ammeters in the cluster?

Nope - Mine has a Volt Meter.

 

[drakon543]

i have a forklift at work with a 1966 chrysler 225 slant 6 a chevy alternator and a 1976 ford f100 voltage regulator in it. who needs all this fancy stuff just cobble something together until it works right!
lol

 

[Captain Insaino]

This is exactly why the auto industry has been dumbing down accurate gauges with feel good-o-meters that don't move until they are out of normal range. They found out some people actually pay attention to them and ask questions they don't want to be bothered with.

 

[iamdub]

This is exactly why the auto industry has been dumbing down accurate gauges with feel good-o-meters that don't move until they are out of normal range. They found out some people actually pay attention to them and ask questions they don't want to be bothered with.

So, next time a cop asks me if I knew how fast I was going, I can honestly and accurately answer "right where it felt good, officer".

 

[George B]

So, next time a cop asks me if I knew how fast I was going, I can honestly and accurately answer "right where it felt good, officer".

Mine doesn’t go fast enough

 

[mbelluardo]

I bought my new Tahoe (2020) a few months ago and today I had to make a 300 mile trip down the interstate. I never really paid attention before but it always seemed to me it was indicating 14 (straight up) but Im sure it moved some. Today I noticed it was move between the straight up position and what I guess would be around 11, it did this several times and I was so paranoid about going dead I didnt even stop for a nature break. If you own a 15 or newer do you ever see your amp meter dropping from te 14 (straight up) to about the 10 or 11 as you go down the highway? It could be its totally normal and I never noticed it but it sure seems odd.

My 2015 Denali xl does that all the time , I also thought it was kinda strange. I’m glad someone brought it up. Just talked to a mechanic friend and yea it’s totally normal.