Shop & toolsShows up, but not every week
Garage door opener
Also called door operator.
A motor, limit switches, a pair of infrared safety beams, and a logic board. The beams are a finished sensor pair.
A donor is the dead machine. The parts below are what is still worth removing from it. “Leave it” is a part that is physically in there and should stay in there: too dangerous, too worn, or only useful as part of a repair you are not doing.
A scrapped machine is a box of parts that failed at different times. The reason it was thrown out is often one bad piece. The motor, the cord, the supply, and the screws are frequently still good. This index says which is which.
Why it is in the trash while the parts are not
A dead logic board, or a remodel. The motor is often fine. The beams are usually fine and people throw them out with the head.
Before you open it
Do this while it is still unplugged, cool, and not leaking. Unplug. The motor is mains. The door spring is a separate mechanical hazard; do not take the spring apart.
Where the dead machine usually is
- Garage and shed — In the house
- Remodel and construction dumpster — Curb
Ask on a remodel. The beams are easy to leave stapled to the rails.
How it comes apart
The cover of the head. Limits are on the rail or on screws at the ends of travel.
Tools: Phillips, Meter.
Words on this page
- mains
- Ordinary household wall power. It can kill. Unplug before you open anything that used it, and do not experiment on live wiring.
What to take
The table is the short version. The notes under it describe that part inside this machine, not only the general description.
| Part | Call | How many | How often | Where to look |
|---|---|---|---|---|
| Single-phase induction motor | Worth pulling | 1 | usually | The head. |
| Phototransistor | Prize | 1 | usually | The safety beam, one side. |
| Infrared LED | Prize | 1 | usually | The other beam. |
| Microswitch | Worth pulling | 2 | usually | Limits. |
| Power relay / contactor | Worth pulling | 1 | usually | The logic board. |
| Indicator LED | Bonus | 1 | usually | The courtesy lamp. |
Prize
Paired with an IR LED on the other side. Polarized, often 12–24 V.
The safety beam, one side.
Keep the pair and the brackets.
Aligned ones are good. Yellowed lenses clean.
The emitter.
The other beam.
Do not swap the pair's polarity.
Good.
Worth pulling
Or a DC motor with a board, on later openers. Mains either way at the cord.
The head.
Read the plate.
Good.
End of travel.
Limits.
Map them.
Good.
Motor reversing.
The logic board.
Read it.
Good.
Bonus
An appliance bulb.
The courtesy lamp.
Not a special part.
Good.