Wis - Lovely - I'm sure actually that the snap - on brick has some codes of its own! ;)
Now then, if its saying loss of communication between Esp & Ecu - and obviously this is can - I suspect its going to be a connection problem on a pin - either at the ecu or the ESP pump. I cant see it being a break midway - pretty unheard of.
It could also be a faulty esp pump - and this is what it is now down too....
So, location of ecu (control module )- is - on the left hand side at the back of engine bay - on left - standing at front of car looking under bonnet (drivers side)
The pump itself is on the passenger side of the engine bay - As I say, I think you need to be inspecting the connections at both the pump and the ecu.
Its worth perhaps pointing out at this stage - the dash warning light flashes to tell the driver that the stability control system is active (a glowing triangle with an exclamation mark inside).
This is why - apart from a bad connection throwing up erroneous messages (light) - that I think the the control unit has gone nuts.
Im going to pop a schematic that I have here for you --- I hope it helps -- but you know where I am if I can help anymore ---------
All the best ---- Mike