12V Digital Car Battery Tester Battery Condition Tester Alternator Charging System Analyzer Battery Test with Cigarette Lighter BST60 Functions: 1. Test all 12V vehicle starting lead-acid batteries. 2. Show real-time voltage and battery charge with the result of LOW/MID/FULL. 3. Test charging system with the result of LOW/OVER/CHARGE, and display the charging voltage in real time. 4. Two options available for testing: Directly plug into the vehicle cigarette lighter socket. Connect the battery terminals with attached alligator clips. 5. Protection of reverse connection and over current, with fuse built-in. Battery Test Battery Test: 1. Keep the engine off. 2. Connect the tester to the battery through alligator clips or cigarette lighter test line, and the battery voltage value will be shown on the screen. Test with cigarette lighter socket: please insert the cigarette lighter of the tester into 12V DC cigarette lighter socket of the vehicle. Test with alligator clips: please connect the red alligator clip of the device to the positive pole (+) of the battery, and connect the black alligator clip to the negative pole (-) of the battery. 3. Turn off all electrical equipments and keep it for a while, and wait for the voltage to stabilize. 4. Press the Battery button to enter the battery test function. At this time, the screen shows the voltage value and the test result. If the LOW light is on, it means that the battery power is very low and needs to be charged as soon as possible. Voltage: <11.8V If the MID light is on, it means the battery power is lower and needs to be charged. Voltage: 11.8V MID <12.5V If the FULL light is on, it means the battery is fully charged. Voltage: 12.5V Charging Test: 1. Please keep the vehicle stationary, increase the engine speed (RPM) to 2500r/min or above, and turn off all electrical equipments, including headlights, air-conditioning fans, glass heating, etc. 2. Press the Alternator button to enter the charging system test function. At this time, the screen shows the charging voltage value and the test result. If the OVER light is on, it means that the generator output voltage is higher. Voltage: 15V. If the LOW light is on, it means that the generator output voltage is lower. Voltage: <13.5V. If the CHARGE light is on, it means the charging system is normal. Voltage: 13.5V CHARGE<15V.