If your vehicle has an ignition problem, the vehicle may just click or it may crank over, depending on which part of the ignition system is malfunctioning. The most common problems are the battery, alternator and starter. You might want to know where to start when the car doesn’t start – after all, just about anything that malfunctions in the engine could cause a no-start, whether the vehicle cranks over or not. If the vehicle only clicks when you try to start it, and you know the engine is not locked up, the first place to check is with the battery, alternator and starter. If you’re of the DIY mindset and don’t want to just take it to your local service department, these are the steps to take to diagnose this issue:
Turn the voltmeter to voltage (20 VDC). Touch the red lead to the battery’s positive terminal. Touch the black lead to the battery’s negative terminal. The voltage should be between 12 and 12.5 volts. If not, charge the battery. The best way to charge the battery is to put it on a battery charger set to low for five to seven hours. Do not charge the battery on high, as you could damage the battery.
Once the battery is charged, test it again with the voltmeter. It should show 12 to 12.5 volts. Start the vehicle. Check the voltage on the battery once more. With the vehicle running, it should show 13.5 to 14.5. Turn on the air conditioning or heater, turn on the lights and radio. Battery voltage should not drop below 12 volts, and should be at 12.5 minimum once everything has been turned on. If not, the alternator is not charging properly and needs to be replaced.
If it is charging, the next test is to see if the battery is putting out enough amps. Have a helper shut the vehicle off. Watch the voltmeter and have the helper start the vehicle. If the voltage drops below 10 volts when the helper starts the car, the battery has a bad cell and needs to be replaced. If the vehicle starts and the voltage does not drop below 11, shut the vehicle off, wait about 30 seconds and start the vehicle again, while watching the voltmeter. If the voltage is still above 10 and rises up to 12.5, the battery is working properly.
If you can’t get the vehicle started even with a freshly charged battery the starter or starter relay is suspect. Put the voltmeter’s red lead on the power wire on the starter and the black lead on a known good ground. Have a helper attempt to start the vehicle. If the voltage is present, power is getting to the starter, which means the starter is most likely bad. If power is not getting to the starter, the relay is malfunctioning, or the wiring (power wire from the battery or the ground wire) has an open (break or bad connection).