Bumping this because the question is still unanswered.
Is there a way to make a regular monitor automatically switch to a different input when switching into reverse (by "regular" I mean one without the 'green wire'). I'm wondering if it's possible to just solder a wire onto the controller board for this or if it is missing circuitry that it needs, is there an external solution?
I don't think this can be done on ANY monitor..
Some Liliputs require soldering in a transistor and a resistor. Some have everything in lpace just the wire is missing.
Mine, for example, just needed the wire soldered:
I could use the buttons the monitor came with, but I don't believe it had a direct input selection, only scrolls through the inputs. I think I will try to find a way to hack an auto switch using info from the thread Max linked. I'd be content with a button to manually switch it, because I'm not taking my mirror out, but I'd insist on a button that could directly select the proper input.
I can't find an external signal switcher that allows composite & hdmi inputs.
The screen i am currently using had five buttons on the front panel along with the IR receiver for the remote. This display does not allow for a direct Input selection either.. Cycle mode of AV1/AV2/PC along with the reverse input that kicks in with the 12volt trigger wire.. But this view is reversed so didnt work for what i needed...
So my option was.... Have the Arduino trigger the button (resistance based button array).. So the Arduino simply presses the button twice in my case, This goes from AV1 to PC.. Then to return press it once instead..
This works providing you find the right resistor value along with getting the timing right. You can also send pulses to the IR line from the Arduino PWM and trigger any remote control function this way.
So maybe have something trigger the button circuit, This works when setup right