3 codes that i cant clear with diagnostic scanner - anyone know what i should be looking at?
Codes that won't clear usually indicate that the fault is still present.
This looks to be new enough to have an adblue system. The adblue fluid can crystallise, blocking feed pipes and injectors. There are ways to clean these, have a browse on YouTube.
An overfilled adblue tank will sometimes leak into the control unit (ECU), which will often result in the need for a new tank. New tanks come as complete units, including the control unit.
Needs more diagnosis before loading any parts cannon.
first warning on dash was water in diesel fuel filter detected??? how is that possible?
Diesel fuel sweats. It absorbs a little water, and so does any air above it in the tank. On cold nights, the water condenses on the walls of the tank, inside, and once the droplets grow large enough, they drain down into the fuel, and drop to the bottom, as the fuel is lighter. This gets pulled through to the fuel filter, which one of the filter's jobs, is to separate this water. There's usually a drain tap or plug on the bottom of the filter housing. Vehicle handbook should show a drain procedure.
A full fuel tank contains little air, so therefore little moisture. Many fleets of trucks and vans fill their tanks each evening, to help prevent water issues. Tedious as an owner, if not using lots of fuel every day.
Petrol does not suffer as much as diesel, diesel seems to attract the moisture.