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How To Check Ignitor With Multimeter? Technician Guide

By Michael

How To Check Ignitor With Multimeter

As an electrical engineer, I love explaining how things like circuits and electronics work. I write on my blog to share simple explanations, reviews, and useful tips about the latest technology.

An ignitor can be diagnosed in various appliances, from gas stoves to furnaces by using a multimeter. Electrical values like voltage, resistance, and continuity can be measured with a multimeter. An understanding of how to check ignitor with multimeter will ensure accurate troubleshooting, potentially saving time and money on the replacement of unnecessary ignitors.  Ignitors are the first thing you need to understand.

What Are Ignitors?

Many gas-powered appliances and equipment rely on ignition components. They play an important role in igniting the fuel-air mixture necessary for combustion. Simply put, they create the spark or heat necessary to light the burner or heating element. 

What Are Ignitors

Types Of Ignitors

1-Spark Ignitors: These are often found in gas stoves, ovens, and some water heaters since they produce an electrical spark to ignite the gas or fuel mixture. A visible spark is produced when they are working properly.

2-Hot Surface Ignitors: Hot surface ignitors ignite gas or fuel by heating up to a high temperature, igniting it when it comes into contact with the hot surface. Modern furnaces and gas-powered heating systems commonly use these.

3-Pilot Light Ignitors: Pilot lights maintain a small, continuous flame that serves as a source of ignition for larger burners. In older gas appliances, they are commonly found.

List Of Required Materials Needed For Checking Ignitor

The materials you'll need to check ignitors with a multimeter must be gathered before you begin. You'll need the following items:

Materials Required For Checking Ignitor
  • Multimeter
  • Safety Gear
  • Screwdriver
  • Replacement Parts (if needed)

How To Check Ignitor With Multimeter?

Test the ignitor if you're an automotive technician diagnosing an ignition system problem. Multimeters can be used to check if the ignitor is working properly. The following is a step-by-step guide on how to check ignitor with multimeter.

How To Check Ignitor With Multimeter

Step#1. Safety Precautions:

Safety Precautions when checking ignitor

Disconnect the vehicle's battery before starting to prevent electrical shock or accidental damage. Avoid exposure to harmful gases by working in a well-ventilated area.

Step#2. Access the Ignitor:

where is the ignitor located in car engine

The ignitor is located within the ignition system. According to the make and model of the vehicle, it is typically located near the distributor or ignition coil.

Step#3. Ignition Key Off:

How To Check Ignitor With Multimeter

In order to prevent accidental engine starts, turn the ignition key to the "Off" position.

Step#5. Connect the Multimeter Probes:

Set your multimeter to DC voltage mode and connect the red probe to the ignitor's power supply wire. In most cases, this wire is labeled "+12V" and provides voltage to the ignitor.

How To Connect the Multimeter Probes to ignitor

Make sure the black (negative) probe is grounded to a good ground point, such as the chassis of the vehicle or the negative terminal of the battery.

Step#6. Record the Voltage:

The ignition key should be turned to the "On" position, but the engine should not be started. You should be able to see a voltage reading on the multimeter. Power supply readings for the ignitor are typically around 12 volts. Power supply problems may occur if the voltage is significantly lower or zero.

Step#7. Test the Ignition Signal:

In order to test the ignitor further, you can measure the voltage on the signal wire, typically labeled "IGT" or "IG-" on the ignitor. The red probe should be placed on the signal wire, while the black probe should be placed on a ground point.

How To Test Signal Wire with Multimeter

Using a multimeter, crank the engine, and you should see fluctuations in voltage, indicating that the ignitor is receiving signals from the engine control module.

Step#8. Interpret the Results:

The ignitor is likely functioning correctly if the voltage readings are within specifications and the signal test passes. If the voltage is out of range or nonexistent, the ignitor may be faulty and needs to be replaced.

Tips For Accurate Testing

Here are some tips to ensure accurate results when testing ignitors with a multimeter:

Tips For Accurate Testing of Ignitor

Tip# 1-Factors Affecting Readings

  • Environmental Conditions: Temperatures and humidity can affect measurements under extreme conditions. You need to select the ventilate area where the temperature is normal.
  • Age and Wear: The ignitor's age and wear can affect readings, so be aware of this when interpreting results. Identify whether it needs to be replaced based on its age.
  • Multimeter Calibration: Maintain the accuracy of your multimeter by calibrating it periodically.

Tip# 2-Techniques for Precise Measurements

  • Probe Placement: Make sure the multimeter probes make good contact with the terminals of the ignitor.
  • Stable Position: Make sure the ignitor and multimeter are in a stable position to prevent fluctuations.
  • Repeat Testing: If you're unsure about the first reading, repeat the test.
  • Consistency: Use the same multimeter settings and techniques for all tests.

Tip# 3-Common Mistakes to Avoid

  • Live Circuits: Never test the ignitor while it is connected to a live electrical circuit.
  • Dirty Probes: Check to ensure that the probes on the multimeter and the ignition terminals are clean.
  • Rushed Testing: Don't rush through the testing process if you want to minimize errors.

Common Ignitor Problems And Solutions

Common Ignitor Problems And Solutions

Ignitor Not Glowing or Sparking

The absence of glow or spark from your ignitor may indicate a malfunction. An ignitor that has worn out or an electrical connection that has been damaged may be the cause of the problem. Consider the following solutions to address this issue:

Inspect for Wear: Ensure that the igniter is free of visible wear and tear. In the event that it appears damaged or cracked, it probably needs to be replaced.

Examine Electrical Connections: Verify that the wires connecting the ignition source are secure and undamaged. A loose or frayed connection can prevent an ignition from working properly.

Delayed Ignition

A delayed ignition may result in appliances taking longer to start or a delayed flame. Several factors could contribute to this issue, including:

Dirty Ignitor: When the ignitor is dirty and debris is present, the ignition can be delayed. It may be resolved by cleaning it.

Weak Spark: The spark ignitor's spark may not ignite the fuel-air mixture if the spark is weak. It may be necessary to replace the ignitor in this case.

Gas Pressure: Check the gas pressure to ensure it's within the recommended range, as low pressure can delay ignition.

Intermittent Ignition

It can be frustrating when appliances malfunction intermittently due to intermittent ignition problems. Consider the following solutions if you are experiencing intermittent ignition issues:

Check WiringThe wiring and connections between the ignitor and the control module need to be examined. It is possible for intermittent ignition to be caused by loose or damaged wiring. Check the wires connected to the ignitor. 

Electrode Cleaning: Clean the electrode tip of a spark ignitor if you have a buildup of carbon that prevents consistent sparking.

Flame Sensor Inspection: Look for carbon deposits in flame sensors from hot surface ignitors. Improved reliability can be achieved by cleaning it.

Ignitor Continuously Glowing or Sparking

It can be hazardous and wasteful to have an ignitor that continues to glow or spark after the burner is lit. Consider the following solutions to resolve this issue:

Flame Sensor Adjustment: If the flame sensor on your appliance is not detecting the flame appropriately, it may need to be adjusted or replaced.

Control Module Inspection: Check the control module for any faults or damage that may be causing the ignitor to stay on.

Gas Valve Check: Check that the gas valve shuts off correctly when the burner is lit. It is possible for the ignitor to remain active due to a faulty gas valve.

When To Replace An Ignitor?

Check the ignitor for bad signs and replace it if necessary. Here are some signs that indicate that the ignitor needs to be replaced.

When To Replace An Ignitor

Signs that Indicate the Need for Replacement

1-Visible Damage: In case the ignitor exhibits visible damage, such as cracks, chips, or excessive wear, it is clearly time to replace it. An ignitor that is damaged is unlikely to function correctly and may even pose a safety risk.

2-Open Circuit: If a multimeter indicates an open circuit (infinite resistance) when testing the ignitor's continuity, then the electrical circuit within the ignitor is broken. Replacement is necessary in this case.

3-Inconsistent Ignition: A malfunctioning ignitor may give intermittent ignition issues, causing your appliance to occasionally ignite and then not ignite. Consistent performance can be ensured by replacing it.

4-Delayed Ignition: When the ignitor fails to ignite the burner or heating element, there is a delay in the ignition process. In order to prevent further problems, it is important to replace the device as soon as possible.

5-Frequent Cycling: When an igniter cycles on and off frequently, it may be malfunctioning. The frequency of cycling affects both the appliance's performance and its energy consumption. The ignitor can be replaced to solve this problem.

6-Excessive Heat Buildup: An ignitor that becomes excessively hot or emits a burning odor may be on the verge of failure. Normally, ignitors get hot, but unusual odors or extreme temperatures should cause concern.


It is true that there are different types of ignitor, but their purpose is the same. It is my hope that my given guide will assist you in understanding How to check ignitor with multimeter.

You are responsible for more money if you do not take action when you notice any bad signs of an ignitor. Do not attempt to replace the ignitor yourself if you aren't familiar with the procedure.