This is my first post here. I have an aftermarket backup sensor that needs to be disabled when I back a trailer. I want to be able to push a button to disable it, but have it be automatically re-enabled when the ignition is cycled. Right now the buzzer is powered by the reverse tail light, but I want the disable device to be controlled by the ignition. Reason being is when I've got a trailer, I may put it in R and D many times (cycling power to the unit), but I'll want the system to be silent until the next time I start the vehicle. So whatever controls it controls the power is NC until I press the button to open the circuit, but then it goes closed when ignition is OFF (or off then on).
I looked for a simple NC latching relay, but it doesn't seem to exist. All latching relays I found required a signal to toggle them between open and closed. The push button will give it the signal to open, but how can I give it a momentary signal to close once the ignition cuts off?
I suppose I can also use a timer relay, but I am hoping to do it the way I described.