The Three Amigos but on the Defender

Hi guys it appears I have the 3 Amigos problem with my TD5 so I'm trying to find the best way to proceed.
First some info on my Vehicle: Defender 90 TD5 XS 03Reg

So the other day (Tuesday to be precise) I started up the beast (after a very wet night). All the dash lights come on fine and then go off above 10kph. Then 300m in the HandBrake, ABS and TC lights come on and stay on.
Pulled over, ignition off and on. Same thing happened and stayed on all the way to work. (checked and had no ABC or TC, braked heavily and floored it from standstill in the wet)
Left it during the day then the same on the way home.
However next day it disappeared and hasn't happened since.
To be cautious i've had a diagnostic scan done and the following codes appeared:
CODE001: Pump failure 1 (monitor line)
CODE002: Pump failure 3 (pump sticking)
CODE003: Shuttle valve switch failure
CODE004: Front Left inlet valve failure
CODE005: Front Right inlet valve short to Ground

These were then cleared but the following codes reappeared:
CODE001: Pump failure 1 (monitor line)
CODE002: Pump failure 3 (pump sticking)
CODE003: Shuttle valve switch failure

Now I have done some research on the problem and the following seems like the best way to proceed, but I would like it confirming/any other suggestions.

1) Brake fluid change (for sticking pump)
2) Check and clean all the sensors.
(will do both of these as part of my service)
3) Buy Shuttle valve repair kit and if problem reappears (ie more lights) then fit it.
After this get another scan. If the problem doesn't reoccur then I will leave the switch and scan.
The one thing i'm not sure about is the first fault code about the monitor line, any ideas what i can do to possibly cure this/find that problem.
If it reoccurs with new switch fluid change etc etc then it's a refurb of my own pump (cannot afford a new one).

Thanks
Will

perhapd first check all connections arent wet ,pump fuse is okay and pump actually works ,sensors never came up in your list so discount them

LR told me my shuttle valve and modulator were definitely bolloxed which was going to be expensive.

Borrow a Nanocom and initiate a brake service cycle of the high pressure circuit. I dont remember what menu option it is but it worked for me when I borrowed Ratty's. Not sure if the Naocom Evos have the same options though. Had hours of fun playing with the more obscure functions.

I cycled the braking system a few times and bled new fluid through each circuit and its been alright for the last two years.

When I went back to LR and tried to explain that they were wrong and how I fixed it by effectively bleeding the brakes I got fcuked off by some snot nosed mechanic who simply quoted the book at me. Needless to say I now dont use or recommend that dealership.