Disconnect power from the radio and remove the bottom cover (requires only removing the 4 screws at the corners). You should see a loop of blue wire protruding through a notch at the front of the unit (if not, you may have to remove the front panel - to do so, pull off the knobs, remove the two screws on top at the front and carefully unsnap).
Once located, cut the loop and properly insulate the ends to prevent a short.
Connect power and turn on the while holding the FUNC key to reset the microprocessor. All settings and memories will return to factory defaults.
Receive coverage will remain 350 to 511.995 Mhz. Transmit coverage will become 400 to 489.995 Mhz. A flashing display indicates PLL unlock, though I have not yet experienced this.