PREVOST LE MIRAGE XLII BUS SHELLS, Руководство по обслуживанию

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Section 01: ENGINE
PA1564
8
code has been stored in the MCM memory.
This light also has a 5-second bulb check when
the ignition is first turned on.
4.1.2 Stop Engine Warning Light (RSL)
This light, also mounted on the telltale light
panel, illuminates to indicate that a major engine
problem is occurring (with the exception of a 5-
second bulb check when the ignition is first
turned on).
4.1.3 Stop Engine Override Switch (SEO)
This switch, mounted on the dashboard, may be
used to extend the 30-second delay period
before engine shutdown when the Stop engine
telltale light is illuminated. This switch can be
repeatedly depressed in order to move the
vehicle out of traffic.
NOTE
The stop engine override switch will be
operative only if it has been depressed before
the end of the 30 second delay period.
CAUTION
The OVERRIDE switch must be used only in
emergency cases, such as to move the
vehicle out of traffic. Excessive use of this
switch can cause serious damage to the
engine.
This switch is also used for DDEC diagnostic
code requests. Press this switch with the engine
at idle or off but with the ignition in the "ON"
position and active codes will be flashed on the
CHECK ENGINE and STOP ENGINE telltale
lights alternately.
4.1.4 Diagnostic Data Link (DDL) Connectors
A connector is mounted on the L.H. footwell
wall. Another connector is located in the rear
electric compartment. They allow the connection
of the Diagnostic Data Reader (DDR) to read
the codes or to access pertinent data on the
condition of the engine. This enables a more
complete analysis of any defect found in the
DDEC system operation. For more information,
see Detroit Diesel Troubleshooting Guide
#6SE492.
4.2 READING DIAGNOSTIC CODES –
FLASHING LIGHT METHOD:
DDEC VI makes use of two types of codes:
Active and inactive. The difference between the
two types of codes is as follows:
Active Codes:
Codes that are currently
keeping the Check Engine or Stop Engine
telltale light illuminated. Active codes are flashed
via the Stop Engine Light when checked with the
stop-engine-override switch.
Inactive Codes:
These are all the codes
logged in the CPC, which have previously
occurred, (whether or not they are currently
turning on the Stop or Check Engine Light).
Inactive codes are flashed via the Check Engine
telltale light when checked with the stop-engine-
override switch.
In most instances, only the DDR can provide the
information necessary for a quick diagnosis of
the problem. If you just need to read out codes,
however, and do not have a DDR available, the
following procedure will let you read out codes.
Make sure the rear-starting switch (located in
the engine compartment) is in the normal
position. With the ignition ON, the engine idling
or engine shut-off, momentarily depress the
Stop Engine Override (SEO) switch. Active
codes will be flashed on the stop engine telltale,
followed by the inactive codes being flashed on
the check-engine telltale panel. The cycle
repeats itself until the operator depresses the
stop engine override switch again.
Flashing codes provide a four digit number.
Each fault code is flashed twice in order to help
with counting the flashes. If there are no active
faults or if there are no inactive faults the
number “3” is flashed once followed by an ~3s
delay.
FIGURE 7: FLASHING FAULTS CODES
Refer to DDEC Troubleshooting Manual 6SE567
for more information and SAE codes.