17
LAUNCH
Professional 909 User Manual
Catalytic
Converter
Monitor
Once per trip
1
2
1
3 trips
40
O
2
Sensor
Monitor
Once per trip
1
2
1
3 trips
40
O
2
Sensor
Heater Monitor Once per trip
1
2
1
3 trips
40
EGR Monitor
Once per trip
1
2
1
3 trips
40
EVAP system
Monitor
Once per trip
1
2
1
3 trips
40
Secondary Air
System
Monitor
Once per trip
1
2
1
3 trips
40
NMHC Monitor Once per trip
1
2
1
3 trips
40
Nox Adsorber
Monitor
Once per trip
1
2
1
3 trips
40
Boost Pressure
System
Monitor
Once per trip
1
2
1
3 trips
40
Exhaust Gas
Sensor Monitor Once per trip
1
2
1
3 trips
40
PM Filter
Monitor
Once per trip
1
2
1
3 trips
40
2.7 DTCs and MIL Status
When the vehicle’s on-board computer detects a failure in an emissions-related
component or system, the computer’s internal diagnostic program assigns a
diagnostic trouble code (DTC) that points to the system (and subsystem) where
the fault was found. The diagnostic program saves the code in the computer’s
memory. It records a “Freeze Frame” of conditions present when the fault was
found, and lights the Malfunction Indicator Lamp (MIL). Some faults require
detection for two trips in a row before the MIL is turned on.
