there's a couple of possibilities as it is switched by the reverse switch in the gearbox.So, if you camera is not working at all, turn on the ignition (do not start the engine), put it in reverse and check if the reverse lights come on.
if they do then next try fiddling with the wiring where it passes over the boot joint (inside a little rubber grommet) as they can fail at this point
and they are also prone to water ingress and there's an updated design so try contacting your dealer about this too
do you still need help?
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