TEST PHONE VIBRATION MOTOR

How to Test a Mobile Phone Vibration Motor

The vibration function in a mobile phone is produced by a small electric motor commonly known as a vibration motor or vibra motor. This motor rotates an off-center metal weight attached to its shaft, creating vibration when electrical power is applied.

Understanding the Vibration Motor

A mobile phone vibration motor is a low-voltage DC motor. When current flows through it, the shaft rotates. Because the metal weight is not centered, the rotation produces a vibrating motion that the user feels when receiving calls, messages, or notifications.

Common Symptoms of a Faulty Vibration Motor

• No vibration during incoming calls or alerts
• Weak or intermittent vibration
• Vibration works only when the phone is shaken

Tools Required

• Analog multimeter (recommended for this test)
• Mobile phone vibration motor (removed or accessible)

How to Test a Vibration Motor Using a Multimeter

Resistance Test Procedure

1. Set the analog multimeter to the X1 resistance (Ω) range
2. Disconnect the vibration motor from the circuit if possible
3. Connect the two multimeter probes to the motor terminals
4. Polarity does not matter for this test

When the probes are connected, a good vibration motor will briefly rotate or twitch. Reversing the probes may cause the motor to rotate in the opposite direction.

Test Results Interpretation

• Motor rotates or vibrates: Vibration motor is good
• No movement at all: Motor is faulty or internally open

Alternative Test Method (Using External Power)

A vibration motor can also be tested using a low-voltage DC power source (typically 1.5V to 3V DC). Momentarily apply voltage to the motor terminals. If the motor spins and vibrates, it is functional.

Safety Reminder

• Do not exceed the rated voltage of the vibration motor
• Apply power only for a short time to avoid damage
• Avoid short circuits on the phone’s PCB

Conclusion

Testing a mobile phone vibration motor is a simple procedure that can quickly determine whether a vibration issue is caused by the motor itself or by the control circuit. Mastering this basic test will help reduce unnecessary board-level repairs and speed up troubleshooting.