A few months back I had a couple of flickering brake light failure warnings but they cleared and I checked all lights were working ok. Last week warning light came on so checked and N/S was out. Got a new bulb and put it in but both stop and tail light not working. I also found the 12v power socket is dead. I took the liner panel out and all connections seem in place. Next step is to check if power is at the 3 bulb terminals but just wondered if it could be a fuse problem? I also found a red cord which hangs down the light unit and goes through a guide towards the rear bulkhead. Any advice please