You get in the car and notice the engine won't start and the headlights won't turn on. After doing the jump-start (starting the engine using another car battery), you need to find out if a new battery or alternator is needed or not. Follow these steps to check the car battery.
Step
Method 1 of 3: Checking the Battery Using a Voltmeter
Step 1. Turn off contacts
Step 2. Open the battery positive terminal cover
Check and clean the battery terminals.
Step 3. Connect the voltmeter positive probe wire to the positive terminal of the battery
The positive probe wire on the voltmeter is usually red.
Step 4. Connect the negative lead of the voltmeter to the negative terminal of the battery
Step 5. Observe the voltmeter
If your battery is in good condition, the voltage should be between 12, 4 and 12.7 volts. A reading lower than 12.4 volts indicates your battery needs to be charged.
- If the measurement results are lower than 12.2 volts, do a trickle charge, which is a slow charging of the battery. Then check again.
- If the measurement exceeds 12.9 volts, you have an overvoltage. Turn on the headlights to eliminate over-voltage charging. Overvoltage can be an indication that the alternator is overcharging the battery.
Method 2 of 3: Checking the Battery Using a Power Probe
Step 1. Open the battery positive terminal cover
Step 2. Connect the Power Probe positive probe wire to the positive terminal on your battery
The positive probe wire on the voltmeter is usually red.
Step 3. Connect the Power Probe negative probe to the battery negative terminal
Step 4. Attach the tip of the gauge to the positive terminal of the battery
Observe the measuring device for voltage measurement results.
Step 5. Observe the measurement results of the Power Probe
If your battery is in good condition, the voltage should be between 12, 4 and 12.7 volts.
Method 3 of 3: Checking the Battery by Cranking the Engine
Step 1. "Crank" the engine by turning the contact until it starts and holding it for 2 seconds
Have someone crank the engine while you check the battery voltage drop.
Step 2. While cranking, observe the measurement results of the Power Probe
The measurement result should not be lower than 9.6 volts.
A battery with a measurement lower than 9.6 volts indicates that the battery has sulfate deposits and cannot accommodate or accept charging
Tips
- Most car batteries last between 4 to 5 years. In hot climates, the battery can last only about 3 years. If you charge the battery and find that the battery cannot accommodate charging when the car is not started, replace the battery.
- If you get a new battery, be sure to dispose of the old battery according to the regulations in force in your country. Usually a parts store can handle battery disposal for you.
- You can check and charge the battery at the nearest spare parts store.
- Before buying a new alternator, inspect the system more thoroughly.
