PREVOST LE MIRAGE XLII BUS SHELLS, Руководство по обслуживанию

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SECTION 01: ENGINE
PA1564
7
Position Sensor (TPS). The (TPS) is a device,
which sends an electrical signal to the Motor
Control Module (MCM). The TPS varies in
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
(Fig. 6). 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 specifications. It is
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 6: ELECTRONIC FOOT PEDAL ASSEMBLY
03035
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
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. DDEC VI DIAGNOSTICS
4.1 DIAGNOSTIC SYSTEM
Diagnostics is a standard feature of DDEC VI.
The purpose of this feature is to provide
information for problem identification and
problem solving in the form of a code. The MCM
and CPC continuously perform self diagnostic
checks and monitor the other system
components. Information for problem
identification and problem solving is enhanced
by the detection of faults, retention of fault codes
and separation of active from inactive codes.
The engine-mounted MCM includes control logic
to provide overall engine management. System
diagnostic checks are made at ignition on and
continue throughout all engine operating modes.
Sensors provide information to the MCM and
CPC regarding various engine and vehicle
performance characteristics. The information is
used to regulate engine and vehicle
performance, provide diagnostic information,
and activate the engine protection system.
The DDEC VI on-board diagnostic system
accessories include the following:
•
Check Engine telltale light (AWL);
•
Stop Engine telltale light (RSL);
•
Stop Engine Override switch (SEO);
•
Diagnostic Data Link (DDL) connectors.
The AWL is illuminated and a code is stored if
an electronic system fault occurs. This indicates
the problem should be diagnosed as soon as
possible. The CPC illuminates the AWL and
RSL and stores a malfunction code if a
potentially engine damaging fault is detected.
These codes can be accessed in one of four
ways:
•
Commercially available J1587/J1939
diagnostic tools.
•
Detroit Diesel Diagnostic Link® (DDDL 7.0).
•
Flashing the AWL and RSL with the
SEO/Diagnostic Request Switch.
•
Dashboard’s Message Center Display
(MCD).
4.1.1 Check Engine Telltale Light (AWL)
The CPC illuminates the Check Engine telltale,
mounted on the telltale light panel to indicate
that a problem has been detected and that a