Diagnostic Trouble Code Type Definition

DIAGNOSTIC TROUBLE CODE (DTC) TYPE DEFINITIONS

EMISSIONS RELATED DTCS

Action Taken When The DTC Sets - Type A
The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.

Action Taken When The DTC Sets - Type B
The control module illuminates the MIL on the second consecutive ignition cycle that the diagnostic runs and fails.

Action Taken When The DTC Sets - Type B1
- The following applies to misfire DTCs:
- If the control module detects a low level or an emission level misfire condition during 2 consecutive trips, the control module illuminates the MIL.
- If the control module detects a high level or catalyst damaging misfire, the control module flashes the MIL at a rate of once per second.
- If the control module detects a misfire during 2 non-consecutive trips, the stored conditions are compared with the current conditions. The control module illuminates the MIL when the following conditions occur:
- The engine load is within 10 percent of the previous test that failed.
- The engine speed is within 375 RPM of the previous test that failed.
- The engine coolant temperature is in the same range of the previous test that failed.
- The following applies to fuel trim DTCs:
- If the control module detects a fuel trim condition during 2 consecutive trips, the control module illuminates the MIL.
- If the control module detects a fuel trim condition during 2 non-consecutive trips, the stored conditions are compared with the current conditions. The control module illuminates the MIL when the following conditions occur:
- The engine load is within 10 percent of the previous test that failed.
- The engine speed is within 375 RPM of the previous test that failed.
- The engine coolant temperature is in the same range of the previous test that failed.

Conditions For Clearing The MIL/DTC - Type A Or Type B
- The control module turns OFF the MIL after 3 consecutive ignition cycles, when the diagnostic runs and passes.
- An active DTC clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Use a scan tool in order to clear the MIL and the DTC.

NON-EMISSIONS RELATED DTCS

Action Taken When The DTC Sets - Type C
- The control module stores the DTC information into memory when the diagnostic runs and fails.
- The MIL will not illuminate.
- The driver information center, if equipped, may display a message.

Conditions for Clearing the DTC - Type C
- A last test failed, or active DTC, clears when the diagnostic runs and passes.
- Use a scan tool in order to clear the DTC.