Monitor Your Own Battery Voltage
Here's an easy way to monitor your car's voltages
without even opening the hood !
JEBSENS USB Phone Charger with Voltage Display
30W Cigarette Lighter Type C and A Charge Ports
Volt Meter Battery Monitor, Compatible with iPhone and Galaxy ~ made by JEBSENS [ LINK ]
To measure Battery Voltage ~ turn car ‘ on ‘, but do not start the engine. In that scenario the battery voltage is displayed. ( 12.4 to 12.8 ~ ok )
To measure the Alternator Voltage ( which charges the battery when the engine is running ) - Start the engine and drive the car. ( 13.5 to 14.8 ~ ok ) . . . Note : a parked car with the engine just idling may not be enough to charge the battery, That’s why it’s best to drive the car while measuring the Alternator Voltage.