Electronic Foot Pedal Assembly (Efpa) & Throttle Position Sensor; Automatic Belt Tensioners And Idler Pulleys Inspection; Bearing Inspection - PREVOST H3-41 Maintenance Manual

SECTION 01 : ENGINE
3. ELECTRONIC FOOT PEDAL ASSEMBLY
(EFPA) & THROTTLE POSITION SENSOR
The Electronic Foot Pedal Assembly (EFPA)
connects the accelerator pedal to a Throttle
Position Sensor (TPS). The (TPS) is a device,
which sends an electrical signal to the Motor
Control Module (MCM).
voltage depending on how far the pedal is
depressed. The system is installed in the space
normally occupied by a mechanical foot pedal.
The (EFPA) has maximum and minimum stops
that are built into the unit during manufacturing
(Figure 13). The (TPS) converts the operator's
foot pedal input into a signal for the MCM.
When installed by the equipment manufacturer,
the TPS should not require adjustment. If the
TPS is suspected of being misadjusted, confirm
that the sensor is installed in accordance with
the manufacturer's
recommended that the idle count be at 50 or
higher with a full throttle count of up to 200.
The TPS is self-calibrating and therefore has no
optimum closed throttle or wide open throttle
count value. If the counts are within the 50 to
200 range, the sensor is properly set.
FIGURE 13: ELECTRONIC FOOT PEDAL ASSEMBLY
Monitor the (TPS) at the controls as you move it
through its full stroke. Be sure there is no
misalignment or obstruction preventing the
smooth movement of the TPS through the full
stroke. Using a diagnostic data reader, check
that the idle and full throttle position counts do
not fall within the error zones. The error zones
PA1615 Maintenance Manual All Series | Section 01 revised April 2017
20
The TPS varies in
specifications. It is
3035
occur when the idle position is less than 14
counts, or when the full throttle position is more
than 233 counts. Should these conditions occur,
the CPC will signal diagnostic codes of 21-12 for
idle error and 21-23 for wide-open throttle error.
4. AUTOMATIC BELT TENSIONERS AND
IDLER PULLEYS INSPECTION
With the engine running, if noise is coming from
the tensioners or drive system, an inspection
with the engine off is necessary.
MAINTENANCE
Remove belts and inspect automatic belt
tensioners, idler pulley bearings at the
intervals specified by the Lubrication And
Servicing Schedule
LUBRICATION & SERVICING.
I= IDLER
T= TENSIONER
FIGURE 14: IDLER PULLEYS AND AUTOMATIC BELT
TENSIONERS ON COOLING FAN DRIVE, WATER PUMP
DRIVE AND A/C COMPRESSOR DRIVE

4.1 BEARING INSPECTION

1. First, set parking brake, turn the ignition OFF
and set the rear start selector switch to the
OFF position.
2. Remove all belts on cooling fan drive, water
pump drive, A/C compressor drive and
alternator drive.
in Section 24:
01225