How to Fix a Garage Door That Won't Close in Sunny Weather

It is one of the most frustrating garage door issues: you press your remote to leave for work on a beautiful sunny morning, but the door starts to close, stops, and immediately reverses back to the open position while the opener light bulbs flash. If this only happens during specific times of the day when the sun is shining directly onto your garage opening, your safety sensors are experiencing sun glare.

Why Sunlight Causes Garage Doors to Reverse

All modern residential garage door openers installed since 1993 are equipped with infrared safety reversing sensors. One sensor (the sending eye) emits an invisible infrared light beam across the opening, while the other sensor (the receiving eye) listens for it. If that beam is broken, the door will not close to prevent injury or damage.

Sunlight contains powerful infrared radiation. When bright sunlight strikes the receiving sensor at a direct angle, it overwhelms the sensor's photocell, blinding it. The sensor can no longer distinguish the sending eye's beam from the ambient sunlight, forcing the opener to default to safety mode and reverse the door.

Simple Fixes for Sensor Sun Glare

Fortunately, you do not need to replace your hardware to solve this issue. Here are the most effective remedies:

• Swap the Sensors: The simplest fix is often swapping the physical positions of the sending and receiving sensors. Move the receiving sensor (usually identified by a yellow/orange LED) to the side of the garage door that receives less direct sunlight during peak hours.
• Build a Sensor Sun Shield: You can create a simple sunshade for the receiving eye. Use a piece of cardboard, a small plastic cup with the bottom cut out, or heavy-duty black tape to build a "hood" around the sensor. This blocks angled sunlight while allowing the straight-line infrared beam to pass through.
• Verify Sensor Alignment: Sometimes, minor misalignment makes the sensors extra sensitive to glare. Make sure the green and yellow LEDs on both sensors are glowing solid, indicating a strong, uninterrupted connection.

When to Call a Professional

If you have shielded the sensors and aligned them but the door still refuses to close, there may be a hairline crack in the sensor wire or internal board failure. A certified technician can quickly test the electrical resistance and install heavy-duty replacement sensors to restore safe operation.