JLG 450A Operation And Safety Manual page 47

12. Engine Start/ Auxiliary Power /Function Enable
To start the engine, the switch must be held
"UP" until the engine starts.
To use auxiliary power, the switch must be
held "DOWN" for duration of function use.
When the engine is running, the switch must
be held "DOWN" to enable all boom controls.
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SECTION 3 - MACHINE CONTROLS AND INDICATORS
13. Machine Safety System Override (MSSO) (CE
Only)
Provides override of function controls that
are locked out such as in the event of Load
Sense System activation.
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