If I push the safety switch then there is no issue, But if i disarmed using safety switch then it will give some PWM to motors and the motor rotates without any reason. This issue is in Arducopter 4.2.2 Quadcopter. Because even I changed the Pixhawk still it happen.
Can you provide a log with LOG_DISARMED set to 1 please? This would be very helpful in determining what might be happening.