Published 2026-05-12 · Houston Garage Door Pros
Garage Door Won't Close in Houston? Start With the Safety Sensors
Quick answer: A garage door that reverses or won't close, with a blinking opener light, is almost always a photo-eye safety sensor problem. In Houston the leading cause is slab settlement: expansive clay soil shifts the slab a quarter inch through the year and knocks one sensor out of line with the other. Wipe both lenses, confirm both LEDs glow solid, and realign until they point straight at each other.
Why Houston slabs cause this
Houston sits on expansive clay that swells when wet and shrinks when dry. The slab corners rise and fall a quarter inch or more through the year, and the photo-eyes at the base of the tracks are bolted to that moving slab. When one side drops, the two sensors stop seeing each other and the opener refuses to close, doing exactly what the safety system is designed to do.
This is the single most common 'won't close' call we get in Houston, and it is usually a five-minute realignment, not a broken opener.
The five-minute homeowner check
Look at both sensors. Both LEDs should glow solid. A blinking or dark LED means misaligned or unpowered. Wipe both lenses with a dry cloth (a cobweb or dust film will do it). Then gently adjust the angle of the blinking sensor until its LED goes solid, and tighten the wing nut.
If both LEDs are solid and the door still will not close, the close-force setting may be too sensitive after a humidity swing, or a spring or cable issue is making the door feel heavier than the opener expects.
When to call
Call if the sensors are clean and aligned but the door still reverses, if a sensor LED stays dark (dead sensor or wiring), or if the door feels heavy when you lift it by hand after pulling the manual release. Our diagnostic is $95 flat, waived on repair.
Frequently asked
Why does my door start to close then go back up?
The safety reverse is triggering, usually from misaligned or blocked photo-eye sensors. In Houston, slab settlement knocking the sensors out of line is the top cause.
Both sensor lights are on but it still won't close. Why?
Either the close-force setting is too sensitive after a humidity swing, or a worn spring or cable is making the door heavier than the opener expects, which trips the obstacle detection.
Can I bypass the safety sensors?
No. They are a federally required safety feature that stops the door from closing on a person, pet, or car. Fix the alignment instead of defeating the sensor.
How much to fix it if I can't?
Sensor alignment or replacement runs $95 to $170. The diagnostic is waived if we do the repair the same visit.
Will this keep happening?
If slab movement is the cause it can recur seasonally. We can adjust the mounting so it tolerates more movement, but significant slab shifting is a foundation issue worth watching.
Related reading
- Opener Repair Service
- Opener Not Working: 12-Point Diagnosis
- Sensor Blinking: Alignment Walkthrough
- Houston Cost Guide