Door will not open fully, stops partway and reverses, Guardian opener LED flashes three times or shows code “3”.

Safety first: Disconnect power before adjusting limits. Do not operate the opener with a visibly damaged door.

• Operate door manually: Pull the emergency release and lift the door fully by hand. Confirm it moves smoothly and clears the header without rubbing.
• Inspect top section: Look for a bent top panel or damaged top strut where the Guardian opener arm attaches. Repair or reinforce the panel if it flexes excessively.
• Check header clearance: Ensure the top of the door is not hitting the header or opener rail. Adjust track brackets or opener mounting if needed.
• Adjust up travel limit: On the Guardian opener, increase the up travel slightly so the door opens fully but does not hit the stops or opener rail.
• Adjust up force (if available): Increase the up force slightly according to the Guardian manual. Do not over-adjust; the door should still stop if obstructed.
• Test several cycles: Restore power and run the door open/close several times to confirm the code clears and the door opens fully without reversing.