I've thought about this as well. However, I wonder IF ... when switching to display the rear camera, maybe the reverse lights would be triggered ON as well. Not a big deal if it does ... just wondering. I haven't pursued it because, the Mirage is so small, I can see behind it good enough.
And, it's not really needed to back up to hitch my trailer either because ... you can't be towing a trailer that can't be lifted at the tongue and sat on the hitch. If the trailer is too heavy to do that, a Mirage shouldn't be towing it.
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View my fuel log 2020 Mirage ES 1.2 manual: 42.4 mpg (US) ... 18.0 km/L ... 5.5 L/100 km ... 51.0 mpg (Imp)