I am going to install 2 garage door openers and I'm stuck on wiring the sensors.

For each garage door I have 1 x 22-2 wire on one side of the door and 2 x 22-2 wire runs on the other side of the door. At the outlet on the ceiling I have 3 x 22-2 wire runs and on the wall by the entry door I have 3 x 22-2 wire runs. I hooked up a tracer to one set of wires by the door and every single wire in my garage that is related to the garage door are all pinging as if signal is going through all of them. Any advice for how to narrow this down or how it might have been prewired for the sensors and control panel?

Power for the opener isn’t an issue.

  • 1
    what do you mean by "3x2-wire runs" and 1x2, etc. I haven't seen that terminology before. Jan 24, 2021 at 22:48
  • If you have a particular type/brand/model of garage door opener planned, download the installation manual to see what is required. My hunch is they likely spec. a 15A or 20A 120V dedicated circuit to the ceiling where the motor is located plus some additional wiring not connected to the 120V power lines running from the ceiling to sensors, control panels, etc. Jan 24, 2021 at 23:06
  • Sorry. I clarified. This is all relating to the sensor and control panel wires. All runs are 22-2 bell wiring. I’m trying to figure out the sensor and control panel pre-wiring. The garage is finished so I’ve only got what they left to work with.
    – Russ W.
    Jan 24, 2021 at 23:10
  • 1
    What is a "tracer"? Do you have an ohmmeter? Make sure no wire pairs are touching; then short one pair and check for continuity on the other end.
    – Mattman944
    Jan 25, 2021 at 0:49

2 Answers 2


You need 2 wires from each sensor. The colors need to be tied together and wired to the opener as the installation instructions show. Usually, the 2 whites are tied together and put on the #2 terminal and the black/white wires are tied together and wired the the #3 terminal. Do this separately for each door. There are 2 sensors for each door and they have to be aimed at and see each other. Read the instructions to be sure of the correct connections. Hope this helps.


Tracers tend to emit signals that migrate to nearby wires, especially flat cables like doorbell wire.

set the tone injector to continuity test mode and see which cable makes it light up when you connect the wires together.

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