Garage Door Won't Open? A Quick Diagnostic Checklist

Quick answer

Five-step check: (1) confirm the opener has power (check the outlet and breaker), (2) look above the door for a visible gap in the tightly wound torsion spring — a snapped spring is the most common cause, (3) try the hardwired wall button as well as the remote to isolate a dead remote, (4) check the two safety sensors near the floor are aligned and their LEDs are lit, and (5) pull the manual-release cord and gently test the door's weight by hand. If it's very heavy or won't stay up halfway, the spring is the problem — stop and call.

Step-by-step

1. Power check. Confirm the opener is plugged in and the outlet has power (a Hill Country storm or a tripped GFCI can kill it). Check the breaker for the garage circuit. If the opener's light comes on but the door won't move, power isn't the issue.
2. Spring check. Look at the spring on the steel shaft above the door. A two- to three-inch gap in the coil means a broken torsion spring — the single most common reason a door won't open. Do not run the opener against a broken spring.
3. Wall button vs remote. Try the hardwired wall control. If the wall button works but the remote doesn't, the remote needs new batteries or reprogramming. If neither works but the opener has power, the logic board or receiver may be the issue.
4. Sensor check. Find the two small sensors near the floor on each track. Both LEDs should be lit and steady. Wipe the lenses, make sure nothing blocks the beam, and gently nudge a bracket if one light is off or blinking — a misaligned sensor stops the door from closing (and sometimes opening).
5. Manual release + weight test. Pull the red release cord to disconnect the opener, then lift the door by hand a foot or two. A balanced door moves easily and stays put. If it's very heavy, slams down, or won't stay halfway, the springs are failing — re-engage the opener and call.

When to call

Call a technician if you see a gap in the spring, the door is heavy or unbalanced by hand, a cable has snapped or the door is hanging crooked, the door is off the track, or the opener motor runs but the door doesn't move. Spring repair and opener repair cover these — most are same-visit fixes.

What NOT to do

• Don't run the opener against a broken spring. The door can weigh 150-350 pounds with no counterbalance; the opener will burn out and a cable can snap.
• Don't try to replace a torsion spring yourself. The stored tension can cause serious injury without winding bars and the correct spring. This is the leading cause of garage-door injuries.
• Don't force an off-track or crooked door. Forcing it drops panels and bends the track further. Leave it and call.
• Don't keep pressing the button when the door reverses. Repeatedly fighting a safety-sensor fault strains the opener — realign the sensors instead.

Need a garage door technician? (830) 293-4770. 24/7 emergency dispatch for a door stuck open or a car trapped inside.