How To Test A Cdi Box With A Multimeter

How To Test A Cdi Box With A Multimeter? Step-By-Step Guide

by

A CDI (capacitor discharge ignition) box is a vital component in the ignition system of a vehicle. It is responsible for generating high-voltage pulses that are needed to ignite the fuel in the engine. A faulty CDI box can cause problems such as misfires, poor fuel economy, and difficulty starting the vehicle. Therefore, it is important to test the CDI box to ensure that it is functioning properly.

Tools Needed

To test a CDI box with a multimeter, you will need the following tools:

  1. A digital multimeter
  2. A spark plug tester
  3. A 12V test light

How To Test A Cdi Box With A Multimeter?

multimeter
multimeter

Here are the steps to test a CDI box with a multimeter:

  1. Disconnect the negative terminal of the vehicle’s battery to ensure safety.
  2. Locate the CDI box. It is usually found near the engine or under the seat of the vehicle.
  3. Set your multimeter to the “Ohms” setting. This setting allows you to measure the resistance of a circuit.
  4. Disconnect the CDI box from the wiring harness.
  5. Test the continuity of the primary and secondary windings of the ignition coil. To do this, touch one lead of the multimeter to the primary winding terminal of the ignition coil and the other lead to the secondary winding terminal. The resistance should be within the manufacturer’s specified range. If the resistance is too high or too low, the ignition coil may be faulty and needs to be replaced.
  6. Test the trigger and stator coils. These coils create the voltage needed to charge the CDI box. To test the trigger coil, touch one lead of the multimeter to the trigger coil terminal and the other lead to the stator coil terminal. The resistance should be within the manufacturer’s specified range. If the resistance is too high or too low, the trigger or stator coil may be faulty and needs to be replaced.
  7. Connect the spark plug tester to the spark plug wire.
  8. Turn the engine over with the starter. The spark plug tester should produce a strong spark when the engine is cranking. If the spark is weak or absent, the problem may be with the CDI box.
  9. Use the 12V test light to test the voltage at the CDI box. Connect one end of the test light to the positive terminal of the battery and the other end to the “charge” terminal of the CDI box. If the test light lights up, it indicates that the CDI box is receiving voltage from the battery.
  10. Test the “discharge” terminal of the CDI box using the same method. If the test light lights up, it indicates that the CDI box is functioning properly.

It is important to follow these steps carefully and accurately to ensure that the CDI box is functioning properly. If you are unsure about any of the steps, it is recommended to seek the assistance of a mechanic or a professional.

Conclusion

I hope this article has helped you understand how to test a CDI box with a multimeter. If you have any further questions, please don’t hesitate to ask.

Leave a Comment