diagnose a car

How to diagnose a car when no crank, no start

In this scenario, either the starter is clicking or nothing is happening. Try turning the lights on. If they are dim, then this is an indicator that the battery is dead and needs a jump or recharge. If the lights aren’t dim, then there is another issue. Use a multimeter to check the voltage on the battery. To do this set the multimeter on the Volts setting and connect the red lead to the positive terminal and the black lead to the negative terminal. There should be 12 Volts at the battery. If there isn’t, recharge the battery or jump the car.

If the voltage is fine, attention should be turned to the starter The goal is to find out if the starter is getting a signal. If the starter is getting a signal, then we know the starter is bad and needs to be replaced, which can also be verified by removing the starter and getting it bench tested at an automotive parts store. To see if the starter is getting voltage:

Place the red lead of the multimeter on the battery lead of the starter and the black lead to ground.

Turn the ignition key while your helper reads the voltmeter display. Is there 12 Volts? If not, the cable from the battery to the starter is bad. If there is 12 Volts, continue.

Disconnect the S-Terminal on the starter. It will be a black connector that plugs into the starter. Remove it and plug the red lead into it and the black lead onto ground. Turn the key while your helper reads the voltmeter display. Is there 12 Volts? If not, the starter isn’t getting a signal. This is most likely due to a bad neutral safety switch. If there is 12 Volts there, then the starter is most likely at fault.

Another issue that plagues many vehicles is corrosion. Be sure to check the battery terminals for corrosion, as well as the negative battery cable where it attaches to the body. If there is any corrosion there, that could be the cause of the vehicle not starting.