Disconnect power from the solenoid circuit
Inspect the solenoid for visible damage, corrosion, or loose connections
Check the coil resistance with a multimeter
Compare the resistance reading to the manufacturer’s specification
Test for continuity across the solenoid terminals
Apply the rated voltage to the solenoid
Listen and feel for a clicking or movement when energized
Measure the voltage at the solenoid terminals while activated
Check for proper mechanical movement of the plunger or actuator
Verify the solenoid returns to its original position when power is removed
Test the solenoid under load if applicable
Replace the solenoid if resistance, continuity, or actuation is outside specification