If your door does not reverse when it meets a 2x4 laid flat on the floor, stop using the opener's automatic close. CPSC says the opener should be disengaged until it is adjusted according to the manual, repaired or replaced. A door that cannot reverse can trap a child or pet, so do not wait.
Why a failed reverse test matters
The reverse system is what stops a closing door when something is in its way. CPSC reports that about 73 children between the ages of 2 and 14 were trapped and killed under automatic garage doors since March 1982, and it says homeowners with openers that do not reverse should repair or replace them.
That is why a failed test is not a nuisance. It means the door could close on a child, a pet or a person. CPSC says to disengage the opener until it is adjusted, repaired or replaced.
Confirm the failure
Clear the area
Keep people and pets away. Open the door fully.
Place a 2x4 flat
Lay a 2x4 flat on the floor, centered under the door. Chamberlain says the door must reverse on a 1-1/2 inch object, which a 2x4 laid flat matches.
Run the door down
Use the wall control and stay clear. The door should stop and reverse as soon as it touches the board.
Note what it did
Did it stop on the board and stay down, keep pushing, or reverse before it reached the board? The answer points to the cause.
Disengage if it fails
Stop using the opener and close the door by hand only if it is balanced, as shown in the manual.
What the symptom usually means
| What you see | Likely cause | Next step |
|---|---|---|
| Stops on the board and does not reverse | The down travel is set too short | Adjust as the manual shows, then retest. See below |
| Reverses before it touches the board | Force or travel set too sensitive, or an obstruction | See why an opener keeps reversing |
| Ignores the photo-eye beam | Sensor dirty, misaligned or failed | Clean and align; see blinking sensors |
| Door is heavy or drops by hand | Spring or cable problem | Stop and call a technician |
A guide to symptoms. Your manual has the exact steps for your model.
Adjusting the travel the right way
Chamberlain's support article says that if the door stops on the obstruction instead of reversing, it is not traveling far enough down, and the down travel should be increased before the test is repeated. It also says to retest after any change and to call a trained door systems technician if the door still will not reverse after repeated adjustments.
Adjust one small step at a time, as your owner's manual shows, and run the test again after each change. On a sectional door the limit setting must not push the door arm past a straight up and down position.
Quick answers
What should I do if my garage door won't reverse?
Stop using the opener's automatic close. CPSC says it should be disengaged until it is adjusted according to the owner's manual, repaired or replaced.
Why does my garage door stop on the 2x4 instead of reversing?
Chamberlain says that usually means the door is not traveling far enough down. Increase the down travel as the manual shows, then retest.
Can I turn up the force so the door closes?
No. Too much force interferes with the safety reversal system, and force adjustments should not be used to compensate for a binding or sticking door.
How often should I test the reverse?
Every month, and after any adjustment or repair to the opener or the door.
What not to do
Do
- Clear obstructions and align the photo eyes first
- Change one setting at a time and retest
- Test again after any repair, spring work or floor repair
- Stop using the opener if the test keeps failing
Do not
- Raise the force to make the door close
- Use force settings to cover a binding or unbalanced door
- Bypass or disconnect the sensors
- Keep using the door because it "mostly works"
Chamberlain says too much force interferes with proper operation of the safety reversal system and that force adjustments should never be used to compensate for a binding or sticking door. If the opener cannot open and close the door, check that the door is balanced and moves freely.
When the opener itself is the problem
CPSC says openers made for sale in the United States after January 1, 1991 must have reversing systems, and that an external entrapment protection system, such as an electric eye or door edge sensor, was added in 1993. An opener older than that should be replaced. A newer opener that cannot be adjusted to reverse may have worn gears, a failed board or sensors that need replacing. See repair or replace an opener and opener repair.
Call a technician
Call if the door still fails after one careful adjustment, if the door is heavy or crooked, or if a spring or cable looks damaged. Our 12-point safety inspection is $89 and covers the springs, cables, rollers, tracks, sensors and opener. We repair doors in cities such as Victorville, Maywood and Woodland. Call (213) 340-4232 or send the estimate form.
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