Users Manual Part 2

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MDMAXLITEA
The boost pressure system serves to increase the pressure
produced inside the intake manifold to a level greater than
atmospheric pressure. This increase in pressure helps to
ensure compete combustion of the air-fuel mixture. The
Boost Pressure System Monitor checks for component
integrity and system operation, and tests for faults in the
system. The computer runs this Monitor once per trip.
The Boost Pressure System Monitor is supported by
“compression ignition” vehicles only. The Boost Pressure
System Monitor is a “Two-Trip” Monitor. If a fault is found
on the first trip, the computer temporarily saves the fault
in its memory as a Pending Code. The computer does not
command the MIL on at this time. If the fault is sensed again
on the second trip, the computer commands the MIL “On,”
and saves the code in its long-term memory.
11. Exhaust Gas Sensor Monitor
The exhaust gas sensor is used by a number of systems/
monitors to determine the content of the exhaust stream.
The computer checks for component integrity, system
operation, and tests for faults in the system, as well as
feedback faults that may affect other emission control
systems.
The Exhaust Gas Sensor Monitor is supported by
“compression ignition” vehicles only. The Exhaust Gas
Sensor Monitor is a “Two-Trip” Monitor. If a fault is found
on the first trip, the computer temporarily saves the fault
in its memory as a Pending Code. The computer does not
command the MIL on at this time. If the fault is sensed again
on the second trip, the computer commands the MIL “On,”
and saves the code in its long-term memory.
12. PM Filter Monitor
The particulate matter (PM) filter removes particulate
matter from the exhaust stream by filtration. The filter has
a honeycomb structure similar to a catalyst substrate, but
with the channels blocked at alternate ends. This forces the
exhaust gas to flow through the walls between the channels,
filtering the particulate matter out. The filters are self-cleaning
by periodic modification of the exhaust gas concentration
in order to burn off the trapped particles (oxidizing the
particles to form CO
2
and water). The computer monitors the
efficiency of the filter in trapping particulate matter, as well
as the ability of the filter to regenerate (self-clean).
The PM Filter Monitor is supported by “compression
ignition” vehicles only. The PM Filter Monitor is a “Two-Trip”
Monitor. If a fault is found on the first trip, the computer
temporarily saves the fault in its memory as a Pending Code.
The computer does not command the MIL on at this time.
If the fault is sensed again on the second trip, the computer
commands the MIL “On,” and saves the code in its long-term
memory.
5.6 Vehicle Voltage
This option allows you to perform a check of the vehicle’s
battery to ensure the system is operating within acceptable