- No power: If both LEDs are off, check low-voltage wiring at the opener terminals and at the sensors. Look for broken staples or loose connections.
- Misalignment: If the receiver LED blinks, adjust the sensor slowly until the LED is solid.
- Sunlight or interference: Direct sun can wash out the beam. Shade the sensor or angle it slightly to avoid glare.
- Damaged wire: Tug gently near each staple. If the LED flickers, repair or replace that wire section.
If the LED never goes solid after careful alignment, the sensor may be failing. You can install new sensors.