Aurora V6-214 3.5L VIN H SFI (2001)
Trip
A trip is an interval of time during which the diagnostic test runs. A trip may consist of only a key cycle to power up the PCM, allow the diagnostic to
run, then cycle the key off to power down the PCM. A trip may also involve a PCM power up, meeting specific conditions to run the diagnostic test, then
powering down the PCM. The definition of a trip depends on the diagnostic. Some diagnostic tests run only once per trip (i.e., catalyst monitor) while
other tests run continuously during each trip (i.e., misfire, fuel system monitors).
Warm-Up Cycle
The PCM uses warm-up cycles to run some diagnostics and to clear any DTCs. A warm-up cycle occurs when the engine coolant temperature rises 22°C
(40°F) from the start-up temperature. The engine coolant must also achieve a minimum temperature of 71°C (160°F). The PCM counts the number of
warm-up cycles in order to clear the MIL. The PCM will clear the DTCs when 40 consecutive warm-up cycles occur without a malfunction.
Diagnostic Trouble Code Display
The DTCs can only be displayed with the use of a scan tool.
Diagnostic Trouble Codes (DTCS)
The PCM is programmed with test routines that check the operation of the various systems the PCM controls. Some tests check the internal PCM
functions. Many of the tests are run continuously. Other tests run only under specific conditions, referred to as the conditions for running the DTC. When
the vehicle is operating within the conditions for running a particular test, the PCM checks certain parameters and determines whether or not the values
are within an expected range. The parameters and the values that are considered outside the range of normal operation are listed as the conditions for
setting the DTC. When the conditions for setting the DTC are present, the PCM executes the action taken when the DTC sets. Some DTCs alert the
driver via the MIL or a message. Other DTCs do not trigger a driver warning, but are stored in memory. Refer to the DTC Type Table for a complete list
of the PCM DTCs and the driver alerts that the DTCs trigger. The PCM also saves the data and input parameters when most DTCs are set. This data is
stored in the Freeze Frame and Failure Records.
The DTCs are categorized by type. The DTC type relates to how the MIL operates and how the fault data is stored when a particular DTC sets. In some
cases there may be exceptions to this structure. Therefore, it is important to read the action taken when the DTC sets and the conditions for clearing the
MIL/DTC in the supporting text when diagnosing the system.
The following list describes the general characteristics of each DTC type:
^
The Type A DTCs are emissions related. The PCM performs the following actions at the time of the first fail:
-
Illuminates the MIL
-
Stores the DTC in memory
-
Captures the Freeze Frame and Failure Records data
^
Type B DTCs are emissions related. The first fail and any subsequent failures are handled differently.
-
The PCM performs the following actions at the time of the first fail:
^
Does not illuminate the MIL
^
Stores the DTC in memory as Failed Last Test
^
Captures the Freeze Frame and Failure Records data
-
The PCM performs the following actions at the time of the second fail if the fault is present for 2 consecutive driving cycles:
^
Illuminates the MIL
^
Stores the DTC in memory and the DTC appears in History
^
Updates the Freeze Frame and Failure Records data
-
The PCM performs the following actions at the time of a second failure that is not on a consecutive trip:
^
Does not illuminate the MIL
^
Stores the DTC in memory as Failed Last Test
^
Updates only the Failure Records data
^
Type C DTCs are not emissions related. The PCM performs the following actions at the time of the first fail:
-
Does not illuminate the MIL
-
Stores the DTC in memory
-
Captures the Failure Records data
-
Some Type C DTCs may also turn on an auxiliary service lamp, and/or cause a message to be displayed on the Driver Information Center
(DIC), depending on how the vehicle is equipped. The lamp or message request occurs at the time of the first fail. The Type C DTCs that do
not turn on a lamp or send a message were formerly referred to as Type D.
DTC Status
When the scan tool displays a DTC, the status of the DTC is also displayed. The following DTC statuses will be indicated only when the statuses apply
to the DTC that is set.
Fail This Ign. (Fail This Ignition): Indicates that this DTC failed during the present ignition cycle. Last Test Fail: Indicates that this DTC failed the
last time the test ran. The last test may have run during a previous ignition cycle if an A or B type DTC is displayed. For type C DTCs, the last failure
must have occurred during the current ignition cycle to appear as Last Test Fail.
