What is normal range for the voltmeter?

[Got_Vnum]

My voltmeter is reading 11.7 - 12.8 volts when cruising (I have a digital voltage gage). I think I remember it being over 13.5 volts before but I'm not sure. I'm just wondering if my alternator is going bad as I have a new battery. Is my voltage too low?

 

[Jerome Sparich]

Too low

My Dodge truck reads 14.3-14.5 when driving

Test you alternator

 

[Slypopsracing]

14.25 just as soon as she fires off,SRT 10, I would be concerned with any less...

 

[Got_Vnum]

Thanks for the verification guys. I guess Ill be needing a new/rebuilt one.

 

[Roadrunner]

Normal charge voltages are 13.5 to 14.75 depending on ambient / battery temperature. 13.5 would be normal for a hot battery or warm to hot ambient temps.

Make sure you are measuring the voltage at the battery though... the voltage will be highest right at the alternator.

Less than 12.5 across the battery (with engine running) probably means the battery is in discharge.... or that the battery is deeply discharged already. But a nice long (hour plus) drive should top off a battery at which time it should be over 13V across the terminals.