XSeries-forum

Replace the part of the injector loom if it's cheap certainly don't be changing any injectors the fact they all show faulty means it's something else most likely.

P = Park lock on the gearbox only.  Parking brake is the switch to the left side of the console by the passenger seat, with the autbrake function (and symbol) button.  That needs separate action.

Sorry for late reply, been away.
The Parking Brake is the lever on the center console, not the Gearbox "p". Effectively what was called the Hand Brake but it's electrically operated.

I've seen a number of posts across a number of forums and there is a You Tube video showing it's replacement.  Mine failed and was replaced but failed again soon after. I suspect the replacement part was the issue as it hasn't had a problem in the last two years since the second replacement.