Picked up a 2001 Kangoo van today as a second vehicle.

The previous owner had the ignition barrel changed as the key broke off inside, so there's 2 keys, one button-fob used to start the car and one without a fob to open the doors.

After starting it twice and then driving it home, I've managed to immobilise it somehow. I was playing with the radio with the key in ignition position 1, no problem, wanted to put ignition 2 on to check the headlights and it's kind of gone dead, no lights on dash, radio won't come on, nothing. Red light on dashboard is flashing away.

Tried a few 'hold the button down' tricks from Googling to no avail.

Any ideas how to fix it?

Ideally I'd like to replace all the door locks to new ones as they are knackered and the key for them is bent and ready to break, and the remote central locking doesn't work but I've no idea where to start, and I can't start it to get it to a garage.