I am working on a project were I would like my Uno to activate the switch on a garage door opener remote control. I have located the contacts on the board of the wireless garage door opener that when the shorted, the opener function is activated. I understand this does not require power and is simply closing the circuit.
I have a Tolako 5v Relay Module w/srd-05vdc-sl-c for my project. What I have tried is to connect my coil to power and the my switch lead to PIN 13 on the Uno. Initially, chose 13 because of the LED so I can tell when it was activated, but now with the relay I hear the clicking. On the opposite side of my relay I connected my leads to the common and Normally Open connections to either side of my switch on my garage door opener remote.
This seems to work as far as when 5V is applied to the switch lead of the relay switches and activates the garage door opener function. The issue is when I power up everything with this setup the garage door opens on boot. I uploaded blank code to the Uno and this continues to happen so it isn’t my code. If I disconnect the switch lead from PIN 13 and just leave the coil powered I hear the rapid clicking on power-up, but no unattended activation of the switch.
This leads me to believe that I am misunderstanding my setup needs. What am I missing? How can I correct this so that I don’t get an activation of the garage door remote upon power up?
See attached sketch.