On drawings, I see two switches side by side near the door. I see an outside light but nothing about the handle lighting.
So is this a new to you or an RV which you know well? Thought is to question if the handle does actually light and what the two switches might do as I would expect one to be for an inside light and one for outside.
The drawing I've snipped and copied shows the left of those two switches to be outside and right being an inside light. The wiring code for the outside shows the bottom wire marked as JF coming from the a 15 amp breaker called circuit 4 and wire PL going to the porch lamp.
The right switch shows wire JC is battery from a different 15 amp breaker on circuit 1 and feeding out to an inside light on wire PJ.
But that is always assuming there has not been a change made in the wiring by previous owners, etc. so approach with a bit of skeptical caution!
If this seems to be what fits your RV, I might pull those switches and check for battery coming in on the lower wires and going out on the upper when the switch is on. If no battery found, then look at the breakers.
This is the wire ID chart and each wire should have a label along the side for the codes.