ECM-26B0 Injector Power Signal too high

[Dude]

Just found this old thread and wonder if anyone can advise?

I'm getting occasional injector codes 2670, 2680 and 26B0 which are injectors 1, 2, 5.

This thread says that's "injector signal too high", however my local Indy garage found a 26B0 reading and report it as "insufficient fuel pressure" (not a VIDA, but better than my basic code reader. I believe VIDA will identify which error when there are more options for a single overall code?)

I've taken a first look at the injector wiring without as yet dismantling much, however, there is clear damage to some wiring (car is an XC70, D5 185, 2006, 144k miles). There's a wire that routes around the offside side of the oil filler cap and its conduit is badly cracked and broken, though the wires look ok for now (I have done a temporary fix). There are also some other injector feed wires I can see where they break out from the loom that have lost their covering. This all suggests that at the age and mileage I would do well to properly check all the injector wiring.

So, questions: (I've never done much on this engine myself, and diesels are a bit of a mystery to me, however, I am reasonably competent, at least to know when to give up and get someone qualified to do it)

1. Which is cylinder 1 - nearside or offside? This seems to be so obvious that nowhere on the net or the Haynes manual does it say. AFAICT, no.1 is offside, left as you look at it standing in front of the car

2. Am I right that to get at the injector wiring (mostly behind the engine?) the sequence is: disconnect battery, remove engine top cover, remove transverse strut (both ends and a connection to the cyl head, then remove the plastic cover above the injectors (into which the top cover hinges) with two nuts either end at the front and twomdown the back of it)?

3. And finally, could water in the fuel cause these codes? The local filling station we use has been out of action, many cars locally reported by our Indy garage with water in the fuel, including my wife's XC60 D5. I have had the fuel filter changed, codes cleared and will see if they come back. My feeling is it's not this, but dodgy wiring.

Thx in advance