Have you been wondering why your engine doesn't start but the headlights and dashboard lights do? The culprit could be the ignition switch. It is the battery that provides power for those lights, and it is the switch that prompts the engine to start. So if you notice this along with other signs of a bad ignition switch, such as a switch that heats up and becomes impossible to touch with bare hands, you should troubleshoot the problem immediately.
Here are the steps in testing and replacing a faulty ignition system switch:
What you'll need:
- Test light
- Screwdriver set
- New ignition switch
Removing the steering column
Step 1: Ensure safety by disconnecting the battery cable from the terminal.
Step 2: With the screwdriver, loosen the screws that hold the steering column in place. If necessary, pry the fasteners as well to take the steering column off.
Unplugging the wiring harness
Step 3: Detach the wiring harness that's connected to the ignition switch. Also unplug the horn wire as well as the retaining nuts and washers. Turn off the windshield wiper and turn signal switches and disconnect their respective wirings.
Testing the switch
Step 4: The best way to do this is through a test light. When you put the key in the start position, the test light should illuminate. The light must turn off when the key is in the off position. If the test light output shows that the switch is working fine, do some troubleshooting to find out what the culprit is. But if the result says that the switch is indeed faulty, proceed with the replacement procedure.
Removing the faulty switch
Step 5: Depending on the vehicle, the switch of your ignition may be held in place by nuts or screws. Loosen and remove them using a screwdriver or a socket wrench. Once released, take the faulty switch out.
Installing the new ignition switch
Step 6: Position the new switch in place of the old one. Turn the switch off and insert the key in the switch. Release the cylinder by depressing the pin that holds it in place. Put the key again to the lock point and then remove the key.
Step 7: If they aren't lined up properly, align all the holes so you won't have a hard time installing and holding the switch in place.
Securing the switch in proper position
Step 8: With the help of a fastener, screw the new switch in place. Reconnect the wiring and re-install the steering column in its proper position. Make sure the ignition cylinder is properly aligned before reconnecting the switches that you've unplugged when you're just starting off with this DIY task. Secure the steering column in place using the mounting screws.
Replacing the ignition switch in modern cars may not be this easy, especially if the ignition is outfitted with additional features such as anti-theft. So it's important to refer to your manual first before deciding to do the task all by yourself.