Casio PAW-1200 has no ABC or atomic time functions?

I have a Casio Pathfinder PAW-1200 which has lost its Altimeter, Barometer and Compass functions, its radio-controlled timekeeping and displays only the briefest flicker of backlight. Trying to access any of these functions results in "Recover" flashing on the otherwise blank display. The battery charge indicator is steady at "H" for high, although I suppose it might be this at fault. Any suggestions welcome, as I've taken G-Shocks apart many times but never a Pathfinder/Protrek. Thanks.