Remote 12v relay / activator - how to wirelessly turn on a remote 12v relay when another 12v circuit is activated

Hi, I am looking for a solution to manage power to a 12v camera on my car, which is directly connected to the battery.

The camera, through the direct connection, is powered constantly and will drain the battery over time, but it only needs to be powered when the car is on. The firewall is difficult to penetrate (BMW Mini), so running wiring to a switched power source in the car isn’t an easy option.

Is there a setup where a relay can be automatically remotely switched on to power the camera when the car is turned on? i.e., the remote activator is wired into the cigarette lighter, which is powered when the ignition is on, which in turn switches on/off the external relay.

Hi @James267995 - welcome to the forums :slight_smile:

There are plenty of really esoteric solutions I can come up with, but none are as simple and reliable as doing it the ‘right’ way - and wiring it into an accessory power distribution that is switched by the key…

Any kind of remote receiver will still drain the battery (though perhaps slower).

Can you help out with any other details? A wiring diagram from a service manual, pictures of the car, location of the camera etc.?