JLG 340AJ Service Manual - Manual (Page 111)

SECTION 3 - CHASSIS & TURNTABLE
3121259 – JLG Lift – 3-71
Multi-Function RPM
Multi-Function RPM occurs when all of the following condi-
tions exist;
1. The Engine State is Engine Running.
2. The operator is not shutting down the engine.
3. High Engine RPM is not being commanded.
4. The control system is not calling for Generator RPM.
5. One of the following conditions exist;
a. Two of the following functions are being operated:
Lift Up, Tower Lift Up, Swing.
b. Telescope is functioning at the same time as one of
the following functions: Jib Lift Up, Platform Rotate,
Platform Level.
High Engine RPM
High Engine RPM occurs when all of the following conditions
exist;
1. The Engine State is Engine Running.
2. The operator is not shutting down the engine.
3. The control system is not calling for Generator RPM.
4. The operator is operating the Drive function at Max
Torque or Max Speed.
5. Drive Forward or Drive Reverse is being operated.
Generator RPM
Generator RPM occurs when all of the following conditions
exist;
1. The Engine State is Engine Running.
2. The operator is not shutting down the engine.
3. The Control System is configured for a generator.
4. The Platform Generator Switch is Enabled and Selected.
3.15 ENGINE CONTROLS
The Kubota and GM engines are both controlled electronically,
but in different manners. The Kubota engine is controlled pri-
marily by the JLG Control System and the GM engine is con-
trolled primarily by its own Engine Control Unit (ECU). The
following sections describe engine controls that are common
to both engines.
Ambient Air Temperature Sensor
The ambient air temperature sensor is integrated within the
Ground Module. The sensor provides temperature information
the engine control system uses to set its fuel, spark, and air set-
tings for engine starting in cold environments.
Fuel Level Sensor
The fuel level sensor is mounted in the fuel tank and consists
of a float device guided by a rod. This rod provides a variable
resistance to ground which is communicated to the ground
module, which in turn, communicates the information to the
operator by way of the fuel level indicator on the platform
console and the low fuel indicator on the ground console.
Figure 3-48. Fuel Level Sensor