volt guage

[tic5850]

I have a2011 Sierra. Have had it for 3 weeks. Yesterday i left work and the volt guage stayed on about 10 volts all the way home. I am thinking that it is discharging. Haven't had time to take it back to the dealer yet. Today it read normal. Am i missing something here? Appreciate your help on this matter. Thanks

Larry

 

[GMC Customer Service]

I have a2011 Sierra. Have had it for 3 weeks. Yesterday i left work and the volt guage stayed on about 10 volts all the way home. I am thinking that it is discharging. Haven't had time to take it back to the dealer yet. Today it read normal. Am i missing something here? Appreciate your help on this matter. Thanks

Larry

Hi Larry,

I’m sorry to hear about the concerns you’re having with your Sierra. I’d agree with you that the best thing to do at this time is to take it to your dealership. If you wouldn’t mind updating us on their findings, I’d appreciate it.

Thanks,
Laura
GMC Customer Service

 

[Z15]

This is NORMAL. The new alternators only charge when they need to.

My 2010 does the very same thing as did my 2008. There is nothing wrong......06 and newer use an Alternator that the output is controlled by the ECM.

When the engine is running, this gage shows the
condition of the charging system. The gage can
transition from a higher to lower or a lower to higher
reading. This is normal. If the vehicle is operating
outside the normal operating range, the charging
system light comes on. See Charging System Light on
page 4‑37 for more information. The voltmeter gage
may also read lower when in fuel economy mode.
This is normal.

 

[tic5850]

This is NORMAL. The new alternators only charge when they need to.

My 2010 does the very same thing as did my 2008. There is nothing wrong......06 and newer use an Alternator that the output is controlled by the ECM.

thanks so much for your help. I have read the owners manual but it just confused me more. Thanks again.

Larry

 

[dirtclod]

tic5850, you can get an inexpensive multimeter (electrical tester) at any walmart or parts store (less than $10). Check your voltage at the battery with the engine not running. Then start vehicle and again take a voltage reading at the battery. A working alternator will raise battery voltage (engine running), at least 1/2 volt ----- to 14 or 16 total volts. In cold weather, mine takes up to 30 seconds after start up, to start charging the battery, so be patient.