Genie GTH-644 Operator's Manual page 48

DANGER
Never operate the machine with a faulty backup alarm. Doing
so may result in serious injury or death.
Place the transmission control lever (A) in reverse. The backup
alarm should sound. If it does not sound, have the backup
alarm repaired immediately.
Check and adjust both the interior rear view mirror (B) and the
exterior right hand mirror (C) if required.
OPERATION
BEFORE OPERATING THE FORKLIFT
A
B
4 - 10
PUMP LOW BRAKE PARKING FRONT REAR
WORKLIGHTS HEADLIGHTS
OFF PRESSURE BRAKE WIPER WIPER
C