Methods and systems for detecting infusion pump conditions

An ambulatory infusion pump system, comprising:

• a reservoir configured to contain a medicament, including a plunger at a proximal end of the reservoir and an outlet port at a distal end of the reservoir;
• a pushrod;
• a motor configured to cause linear motion of the pushrod to contact and move the plunger to cause medicament to flow from the reservoir out of the outlet port to a patient;
• an optical encoder configured to monitor a linear position of the pushrod;
• and
• a processor configured to control the motor and pushrod to cause delivery of medicament from the reservoir, wherein the processor is configured to:
• command the motor to actuate to deliver medicament from the reservoir by advancing the pushrod from a first linear position to a second linear position;
• monitor a move completion time for the pushrod to advance from the first linear position to the second linear position;
• compare the move completion time to an expected move completion time;
• and
• notify a user of an error if the monitored move completion time is longer than the expected move completion time.