Showing 10-11v gauge battery at 13.9

[ja_racing]

Comanche 90 any suggestions showing inside gauge at 10-11v with blower motor on and lights any tips to get it higher test it at the battery and its at 13.9v annoying that my rem keeps throwing code for low voltage 

[AZJeff]

For starters, do NOT rely on the guage on the instrument panel to give you accurate voltage readings.  Instead, measure the voltage on the battery terminals directly using a VOM.

 

Additionally, with the blower on full tilt and with all exterior lights on, those devices probably draw more current than your alternator can deliver at idle.  That would cause a less than fully charged battery to begin to show a voltage slump.

 

this can be confirmed by running engine RPM up to 1500 or higher, and measuring battery voltage with a VOM while all of those devices are turned on.

[ja_racing]

22 minutes ago, AZJeff said:

For starters, do NOT rely on the guage on the instrument panel to give you accurate voltage readings.  Instead, measure the voltage on the battery terminals directly using a VOM.

 

Additionally, with the blower on full tilt and with all exterior lights on, those devices probably draw more current than your alternator can deliver at idle.  That would cause a less than fully charged battery to begin to show a voltage slump.

 

this can be confirmed by running engine RPM up to 1500 or higher, and measuring battery voltage with a VOM while all of those devices are turned on.

I'm measuring at the battery with a volt meter and it reads from 13.9v-14v with ac full blast and all lights on at night i have a higher amp alternator i know I'm fine, i don't care for the gauge to much but i have nicks rem device and throws a code for low voltage i might just look into how to correct the volt reading on the diagnostic port so it doesn't throw the code

[eaglescout526]

Grounds grounds grounds. Make sure they’re all clean and new ones added and old ones replaced if needed. 

[ratrapp]

the 88 i had showed a good volt less than what it actually was.my grandmother bought it when it was a year old with only 10k miles on it and it had always been off some.factory gauges arent always the most accurate.

[AZJeff]

I will admit I am not familiar with how the REM device actually measures voltage, so I cannot comment on why you are seeing that device reporting low voltage while the battery is just fine.

 

sorry

[Ωhm]

What is Battery Voltage (VLT) on the REM?