after a power outage, my nexx is online but the app says 'door obstruction detected' and won't close.

Diagnosis

The "door obstruction detected" error in the Nexx app is not actually a failure of the NXG-200 controller itself, but rather a report of a "break" in the safety circuit of your primary garage door opener. When a power outage occurs, the sudden surge or the subsequent reboot can cause the opener's logic board to trigger a safety fault. More commonly, the physical vibration of the door moving during a power flicker or the slight shift in the garage structure can knock the infrared (IR) safety sensors out of precise alignment. The Nexx controller monitors the state of the door via its magnetic reed sensors. If the opener's internal safety system prevents the door from closing (due to the IR beam being interrupted), the Nexx detects that the "Close" command was sent but the door didn't move, or it receives a fault signal from the opener. To confirm this, look at the physical safety sensors located about 6 inches off the ground on your door tracks. If the LED on the receiving sensor is flickering or completely dark, the circuit is open, and the opener is programmed to refuse any "Close" command for safety reasons, which the app then reports as an obstruction.

How to Fix It

You must resolve the physical sensor issue before the app will allow you to operate the door. Follow these exact steps:

1. Locate the two safety sensors at the base of your garage door tracks. Identify the "sending" sensor (connected to the power source) and the "receiving" sensor (the one that captures the beam).
2. Check the LED indicator on the receiving sensor. A solid green or amber light indicates a clear path. If the light is blinking or off, the beam is misaligned.
3. Loosen the mounting bracket screws slightly using a Phillips head screwdriver. Gently pivot the sensor bracket until the LED light stops blinking and remains solid.
4. Tighten the bracket securely to ensure the sensor does not shift again. Ensure there are no cobwebs, dust, or debris covering the lens of either sensor, as these can scatter the IR beam.
5. Perform a "Hard Reset" of the Nexx controller to clear the cached error state. Unplug the NXG-200 from the power outlet for 30 seconds, then plug it back in.
6. Open the Nexx app and attempt to close the door. The "obstruction detected" message should now be gone.

If That Didn't Work

• Test the Manual Override: Press the physical wall button inside your garage. If the door still refuses to close, the issue is 100% with your opener's sensors or wiring, not the Nexx. If the wall button works but the app doesn't, the Nexx is likely experiencing a synchronization lag and requires a full factory reset by holding the pairing button for 10 seconds.
• Inspect the Sensor Wiring: Power outages can occasionally coincide with electrical surges that fry the thin 22AWG bell wire connecting the sensors. Inspect the wires for any signs of fraying or corrosion. If a wire is pinched against the track, the circuit will remain "open," triggering the obstruction error.
• Check for "Ghost" Obstructions: Ensure no cardboard boxes, trash cans, or seasonal decorations have shifted during the power event and are now blocking the beam. Even a small piece of hanging string or a spiderweb directly in front of the lens can trigger this fault.
• Verify Magnetic Sensor Placement: Ensure the Nexx magnetic reed sensor (the small white piece on the door) is still within 0.5 inches of the controller unit when the door is closed. If the magnet shifted, the Nexx may believe the door is in an indeterminate state, causing it to misinterpret the opener's safety fault.

Heads Up

• Surge Protection: To prevent future logic errors after power outages, plug your NXG-200 and your main garage door opener into a high-quality surge protector.
• Sensor Cleaning: Wipe your IR sensor lenses with a microfiber cloth once every six months; dust accumulation is the leading cause of intermittent "obstruction" errors.
• Avoid Force-Closing: Do not attempt to bypass the safety sensors by jamming the wall button; this can burn out the opener's motor or damage the Nexx relay.
• Firmware Updates: Check the Nexx app for any pending firmware updates for the NXG-200, as newer versions improve how the device handles "False Positive" obstruction reports.