Your step-by-step troubleshooting guide.
The Quick Answer
Most often, a garage door that won’t close is due to misaligned or obstructed safety sensors. Other common causes include something blocking the door’s path, misaligned tracks, or a problem with the remote control’s batteries. Start by checking the safety sensors first.
Troubleshooting Checklist
1. Check the Safety Sensors
These small boxes on either side of your garage door near the floor prevent it from closing on an object. This is the #1 cause of closing issues.
- Check for Obstructions: Make sure nothing is blocking the sensor’s beam. Even a spiderweb can cause an issue.
- Look at the LED Lights: Both sensors should have a solid, lit LED (usually green or amber). If one is blinking or off, they are misaligned.
- Align the Sensors: Gently adjust the blinking sensor until its light becomes solid. You may hear a “click” when it’s aligned.
- Clean the Lenses: Wipe the sensor lenses with a soft, dry cloth.
2. Look for Physical Obstructions
The door will automatically reverse if it hits an object in its path. Check for anything that could be in the way.
- Inspect the garage floor directly under the door.
- Check the metal tracks on both sides for debris, dirt, or objects.
- Ensure items stored near the door haven’t fallen into its path.
3. Inspect the Door Tracks
The tracks guide the door’s rollers. If they are bent or out of alignment, the door can get stuck.
- Visually inspect both vertical and horizontal tracks for bends or damage.
- If you see a minor bend, you can sometimes gently tap it back into place with a rubber mallet. For major damage, call a professional.
4. Check Remotes and Power
Sometimes the issue is with the signal or power source.
- Try closing the door using the wall-mounted button. If it works, the problem is likely your remote.
- Replace the batteries in your remote control.
- Make sure the opener unit is plugged into a working outlet.
When to Call a Professional
Safety First: If you suspect the problem is with the springs or cables, stop immediately. These parts are under extreme tension and can be very dangerous.
- Broken Springs: If you see a gap in one of the large springs above the door.
- Frayed or Broken Cables: If the metal cables that lift the door are damaged.
- Severely Bent Tracks: If the tracks are significantly damaged.
Frequently Asked Questions
How do I reset my garage door safety sensors?
To reset them, ensure they are aligned (both LEDs solid). Then, disconnect power to the opener for about 15 seconds and plug it back in. This often resets the system.
What does a blinking light on my garage door opener mean?
A blinking light is an error code. Most commonly, it indicates a problem with the safety sensors. Check your owner’s manual for the specific code.
Can I fix a broken garage door spring myself?
Never. Springs are under extreme tension and can cause severe injury. Always call a qualified professional for spring replacement.
Written by Dmytro Shevchenko, Certified Garage Door Technician in PrimeGDR.
Last updated: September 24, 2025
Dmytro Shevchenko is the owner of Prime Garage Door Repair, a trusted garage door repair company serving the Chicagoland area. Based in Mundelein, IL, he leads a team of certified technicians specializing in emergency repairs, opener and spring replacement, and complete garage door installation.
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