Komatsu GD555-5 Operation & Maintenance Manual page 170

OPERATION OPERATION
3. Set gear shift lever (4) to the P (PARKING) position while
pressing its knob. The parking brake lamp lights up at the same
time.
WHEN SELECTING TORQUE CONVERTER AUTO MODE
1. Release accelerator pedal (1).
2. Depress brake pedal (2) and stop the machine.
OPERATION OPERATION
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