Voltage When the Car is Stopped (Engine Off):

• 12.6 volts or above: Fully charged and healthy battery.
• 12.4 volts: About 75% charged. Battery should be recharged soon.
• 12.2 volts: About 50% charged. Recommended to charge to avoid starting issues.
• 12.0 volts: Reflects a 25% charge. May not start reliably.
• 11.9 volts or below: Discharged or dead. Charge or replace immediately.

Voltage When the Car is Running (Engine On):

• Typical Range: 13.7 to 14.7 volts, indicating proper charging.
• Below Normal: Voltage under 13.7 volts may indicate a charging system issue.
• Above Normal: Voltage above 14.7 volts may suggest overcharging, which can damage the battery and electrical components.

Voltage Drop During Starting:

• Normal Range: Voltage drops to 9.6 to 10 volts during starting.
• Below 9.6 Volts: May indicate a weak or aging battery.

After the Engine Starts:

Once the engine starts, the voltage should rise to 13.7 to 14.7 volts as the alternator recharges the battery.

Monitoring and Maintenance:

• Battery Health: Check voltage during starting to gauge battery strength.
• Starting System Check: Ensure the battery, starter motor, and alternator are functioning correctly.

Why Car Voltage is Essential:

• Engine Start: Adequate voltage ensures the starter motor can crank the engine.
• Electrical System Health: Proper voltage is critical for the functioning of electronics in the vehicle.
• Battery Lifespan: Monitoring voltage helps detect early signs of battery or electrical system issues.
• Fuel Efficiency and Performance: Proper voltage supports optimal fuel combustion and engine performance.
• Safety: Ensures that safety features operate correctly.
• Prevents Electrical Overload: Maintains voltage within a safe range to protect electrical components.