Following on from my last question about gearbox levels on my 1999 XKR, while I was carrying out this work I left the key in the ignition for a week or two (I know.....) and managed to flatten the battery.
Nothing daunted, I disconnected it and hooked it onto my battery charger, which has brought it back to life.
So back on the car and hooked up, starts up fine, but it's telling me that I have Traction Control and Stability Control faults.
There were no faults at all before this foolishness, so I'm guessing that some systems need to be reset somewhere; can someone please point me at the appropriate information?

 

A hard system reset is to remove the negative cable from the battery post and touch the cable to the positive post. That drains all the residual electrons hiding in various capacitors. That fixes a lot of strange electrical issues. If it doesn't, check the battery voltage while starting, effectively doing a load test. The starter is capable of rotating the engine dragging the voltage below what some systems will tolerate.

 

Yep, that did it; all is now sweetness and light again!
Cheers,John