Chrysler Sebring 2005 Service Manual page 2180

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TASK MANAGER (Continued)
The Task Manager Screen shows both a Requested
MIL state and an Actual MIL state. When the MIL is
illuminated upon completion of a test for a good trip,
the Requested MIL state changes to OFF. However,
the MIL remains illuminated until the next key
cycle. (On some vehicles, the MIL will actually turn
OFF during the thirdgood trip) During the key cycle
for the third good trip, the Requested MIL state is
OFF, while the Actual MIL state is ON. After the
next key cycle, the MIL is not illuminated and both
MIL states read OFF.
Diagnostic Trouble Codes (DTCs)
With OBD II, different DTC faults have different
priorities according to regulations. As a result, the
priorities determine MIL illumination and DTC era-
sure. DTCs are entered according to individual prior-
ity. DTCs with a higher priority overwrite lower
priority DTCs.
Priorities
• Priority 1 One-Trip Failure of Non-Fuel or Non-
Mis-Fire Fault (e.g., Cat Mon Failure)
• Priority 3 Matured Fault (either One-Trip or
Two-Trip) Non-Fuel & Non-Mis-Fire
• Priority 4 One-Trip Failure of Fuel System or
Mis-Fire Fault
• Priority 6 Matured Fault for Fuel System or
Mis-Fire (either One-Trip or Two-Trip)
Non-emissions related failures have no priority.
One trip failures of two trip faults have low priority.
Two trip failures or matured faults have higher pri-
ority. One and two trip failures of fuel system and
misfire monitor take precedence over non-fuel system
and non-misfire failures.
DTC Self Erasure
With one trip components or systems, the MIL is
illuminated upon test failure and DTCs are stored.
Two trip monitors are components requiring failure
in two consecutive trips for MIL illumination. Upon
failure of the first test, the Task Manager enters a
maturing code. If the component fails the test for a
second time the code matures and a DTC is set.
After three good trips the MIL is extinguished and
the Task Manager automatically switches the trip
counter to a warm-up cycle counter. DTCs are auto-
matically erased following 40 warm-up cycles if the
component does not fail again.
For misfire and fuel system monitors, the compo-
nent must pass the test under a Similar Conditions
Window in order to record a good trip. A Similar Con-
ditions Window is when engine RPM is within ±375
RPM and load is within ±20% of when the fault
occurred.
ON-BOARD DIAGNOSTICS
NOTE: It is important to understand that a compo-
nent does not have to fail under a similar window of
operation to mature. It must pass the test under a
Similar Conditions Window when it failed to record
a Good Trip for DTC erasure for misfire and fuel
system monitors.
DTCs can be erased anytime with a scan tool.
Erasing the DTC with the scan tool erases all OBD
II information. The scan tool automatically displays a
warning that erasing the DTC will also erase all
OBD II monitor data. This includes all counter infor-
mation for warm-up cycles, trips and Freeze Frame.
Trip Indicator
The Trip is essential for running monitors and
extinguishing the MIL. In OBD II terms, a trip is a
set of vehicle operating conditions that must be met
for a specific monitor to run. All trips begin with a
key cycle.
Go o d Trip
The Good Trip counters are as follows:
• Global Good Trip
• Fuel System Good Trip
• Misfire Good Trip
• Alternate Good Trip (appears as a Global Good
Trip on scan tool)
• Comprehensive Components
• Major Monitor
• Warm-Up Cycles
Glo ba l Go o d Trip
To increment a Global Good Trip, the Oxygen sen-
sor and Catalyst efficiency monitors must have run
and passed, and 2 minutes of engine run time.
F u e l S y s te m Go o d Trip
To count a good trip (three required) and turn off
the MIL, the following conditions must occur:
• Engine in closed loop
• Operating in Similar Conditions Window
• Short Term multiplied by Long Term less than
threshold
• Less than threshold for a predetermined time
If all of the previous criteria are met, the PCM will
count a good trip (three required) and turn off the
MIL.
Mis fire Go o d Trip
If the following conditions are met the PCM will
count one good trip (three required) in order to turn
off the MIL:
• Operating in Similar Condition Window
• 1000 engine revolutions with no misfire
Alte rn a te Go o d Trip
Alternate Good Trips are used in place of Global
Good Trips for Comprehensive Components and
Major Monitors. If the Task Manager cannot run a
Global Good Trip because a component fault is stop-
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