TDC 1 Boot sequences Keys must be pressed together at the same time. Warm Boot Func. + L, then on Cold Boot F1 + F4 + enter, then on If unit locks up. Connect to external power supply and then remove 9 volt batteries. Unit should shut down. Then perform warm boot procedure. The key strokes for the warm boot may need to be repeated several times. This should restore the unit to working condition. **WARNING** Cold boot will erase all data, data dictionaries, and internal settings.