How to Test Ignition Switch With a Multimeter

In fact, an ignition switch is used in the control system of a motor vehicle. The key tends to switch on the car’s electrical operation incorporating the power window and the stereo. Along with the name ‘Ignition Switch’, it is also called a start switch or a starter switch. That means this key powers the ignition system and starter solenoid. Particularly, this works in cars with inner combustion motor engines.

However, as a car owner or as a car mechanic, you may often fall into the problem of how to test an ignition switch. Yet, there are several ways to solve it. But, today I’ll talk about the most convenient one. That is, how to test an ignition switch with a multimeter. 

Let’s get started then. I’ll let you know:

  • How to test ignition switch using a multimeter
  •  Signs Of A Faulty Ignition Switch
  • Essential Tools Needed To Test Ignition Switch 
  • Technique 1
  • Technique 2
  • Technique 3

How to test ignition switch using a multimeter

Do you have a multimeter? If you do not, take one as per requirements from Amazon

If you ask me to suggest, I would recommend using this Multimeter from Amazon. Check it in a while.

If your ignition switch comes with some problematic issues, then it can result in some difficulties for you. Then, how to know what are the faults in your switch or how can you recognize that there are some issues with your ignition keys? These are some signs of that. 

Signs Of A Faulty Ignition Switch: 

  • Your vehicle is stopping unexpectedly.
  • Your vehicle is denying you access. 
  • Your car stands straight after being started.
  • There have been problems while activating the accessories.

As said earlier, you can never power on your car engine without an ignition switch. There are some vehicles that installed the ignition switch as a part of an anti-theft operation. 

My recommendation is to get a multimeter for testing whether your ignition switch is functioning or not. A question may come from the other side, why should I use a multimeter? You should use a multimeter as it checks for both AC and DC voltage, resistance, and current. 

Here, I’m showing multiple techniques that you can utilize to examine the working ability of an ignition switch. In doing so, you can use not only a digital multimeter but also an analog one as well.

Essential Tools Needed To Test Ignition Switch: 

A MultimeterMultimeter

A Replacement Ignition Switch.

An Automotive Wiring Diagram.

A 12 Volt Test Light

Technique 1

  1. Set your fuse panel under the steering wheel. Then, open it. Snatch the starter signal’s fuse. You can do it by taking the fuse pullers positioned on the fuse panel.
  1. Now, cautiously scan your metal strip. Then, assure that it hasn’t got destroyed or flushed. Once your fuse gets destroyed, change it with an operational element of the same intensity as the aforesaid one.
  1. Roll the dial on a digital multimeter to the “volts” indication once your car’s hood is opened. Keep the black lead on the digital multimeter to the covering of your car as well as the positive port of the battery. Connect the red lead of the multimeter. If your battery is good enough to function, the voltage is supposed to be nearly 12.6 Volts.

If you want one great 12 Volt Test Light. Check my recommended one from Amazon. 

If the voltage is slighter than 12 volts, then you have to replace the battery. Perhaps, your battery is not functioning or it’s deceased. Power up the engine by using the ignition key within the ignition switch. As you have come to know that the ignition switch is working well when you can get your engine starting appropriately.

And when the engine is not being started, twist the ignition key to the (III) direction. Provided that it is not getting started even, then check whether there is any clicking noise. If you can hear any sound, then there should be some problem in your car. However, don’t worry, this time the problem is not with your ignition switch. 

On the other hand, if there is a clicking tone while keeping the ignition key at (III), as well as your engine is not working, then be sure that your ignition switch has broken. Like this, you will have to renovate your ignition switch.

Technique 2

To know what your car’s wiring diagram is, you have to know it. You can simply get it by checking Automotive Wiring Diagrams. Automotive Wiring Diagrams

  1. Discard one wire, then lift an old spark plug to the end of the plug boot. After that, search for a metal surface on the engine. As soon as you have put the keys into the switch, power on the vehicle engine. Now, check for a spark on the old spark plug. Assuming that you don’t find any spark on the plug, then it is very sure that the ignition switch needs a change certainly.
  1. You can simply do it by having your multimeter on. Look what’s the voltage reading is there in the positive end. Do it keeping your key in the switch, and having your ignition switch on. After that, position the red lead on the positive end of the coil. Besides, spot the black lead of the voltmeter on the negative battery terminal, place the black lead of the voltmeter. After that, keep the ignition in the run position once it is turned on. When your ignition switch is operating properly, you should find the voltage of your battery showing in the positive end. On the other hand, when you can’t get any voltage reading, or there is very low reading, it is not a good sign. It indicates that there are some troubles in ignition wiring or the ignition switch.
  1. Place the positive cable of the ignition. Then, swivel the ignition key to the ‘run’ direction. Don’t turn on your engine just after that. Grip the multimeter’s red lead. After that, tug the ignition module wire through it. Make sure that your battery’s voltage is scanning at the cable. When you don’t find any voltage reading, probably here is an open circuit in between your ignition switch and the wire.
  1. Operate the negative cable into the red lead of your multimeter. Then, you should deduct the cap on the distributor. But, you should do it without bringing out the spark plug cables. Power on the engine, or fluctuate the center shaft on the distributor by your hand. Check the distributor rotor sharply as your engine starts moving. When your rotor isn’t turning, your distributor isn’t functioning. At this point, the multimeter should be reading zero or the battery’s voltage if the ignition switch and the distributor are working. When the multimeter can’t display the valid voltage, your ignition switch may be changed.

Technique 3multimeter is functioning

  1. Make sure that the multimeter is functioning by swerving the resistance to “XI.” It occurs once you turn on the multimeter as well as select the ohm function. Assuming that, there is a zero resistance, then the VOM is still performing.
  1. Then, swivel your ignition key until it gets on to the off state. Keep the positive lead to the rear side of your ignition switch’s power supply cable. And keep the multimeter’s negative lead to the surface base of the distributor.
  1. Check the battery’s voltage with the multimeter. Make sure that the ignition key is at the state on your ignition switch. When you get the reading is around 90% of the voltage of your battery, then there’s something wrong in the ignition system.

Wrapping Up! 

Hopefully, you have already solved this problem. If you have anything to know, then let us know in the comment section below. And if you have any more questions on how to test an ignition switch with a multimeter, then feel free to ask us below.

Being back within a short time.

Best regards!

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