Cali 12v electrics

[brad63]

Having trouble with rear lights and 12v cig lighter by seat/rear bed.

I have intermittent lights above the kitchen I.e both LEDs and the fluorescent. I have good earth bad power but sometimes when left switched on the LEDs come on, I thought I had a poor wire connection. I have recently found that the cig lighter by the rear bed also has no power.
My van is a 06 and left had drive I have hela plug infront of sink which works, cig lighter not working by seat and mag strip under the bed which I don't have a connector to test. I have all interior lights on the sliding door side. Wire diagram is suggesting this is a loop in loop out wire system :s

Any ideas of fixes fuses to try I have been to the 10amp for rear lights under seat and is good obviously I have half of the lights. is the verdict running new wires ? Thanks brad.