GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Saturn 🢒 2004 🢒 ION 🢒 Transmission/Transaxle 🢒 Manual Transmission - Getrag 5 Speed 🢒 Diagnostic Trouble Code (DTC) Type Definitions

Diagnostic trouble codes (DTCs) are categorized into emissions and non-emissions related types. If a DTC is set, the malfunction indicator lamp (MIL) and failure data are utilized by the control module diagnostic executive according to the DTC type. Each DTC is set based upon the individual DTCs running and setting criteria. Read the Action Taken When the DTC Sets and Conditions for Clearing the MIL/DTC in the supporting text for taking appropriate action to each DTC. All DTCs can be cleared with a scan tool. Only clear DTCs when instructed to do so in the diagnostic table.

Emissions Related DTCs

Type A

The following actions occur at the time of the first failure:

    • The MIL is turned ON.
    • A DTC is stored in memory.
    • The Freeze Frame/Failure Record data is stored.
    • The Failure Records are updated after the first failure of each ignition cycle.

Some Type A DTCs will not perform the above actions when the DTC first detects a failure. Two consecutive failures are required. This allows systems, such as evaporative emission (EVAP), to accurately identify what failure exists before setting a DTC and requesting MIL illumination.

Type B

The following actions occur at one of the following times:

    • First failure:
       - The MIL is not turned ON.
       - A DTC is stored in memory as a Failed Last Test.
       - The Failure Record data is stored.
    • Second consecutive drive cycle with a failure:
       - The MIL is turned ON.
       - A DTC is stored in memory as a history DTC.
       - The Freeze Frame data is stored.
       - The Failure Record data is stored.
    • Second non-consecutive drive cycle with a failure:
       - The MIL is not turned ON.
       - A DTC is stored in memory as a Failed Last Test.
       - The Failure Record data is stored.

Non-Emissions Related DTCs

Type C

The following actions occur at the time of a failure:

    • The MIL does not turn ON.
    • The driver information center will display SERVICE VEHICLE.
    • A DTC is stored in memory as a history DTC.
    • The Failure Record data is stored.
    • The Failure Records are updated after the first failure of each ignition cycle.

Type D

The following actions occur at the time of a failure:

    • The MIL does not turn ON.
    • The driver information center will not display SERVICE VEHICLE.
    •  A DTC is stored in memory as a history DTC.
    • The Failure Record data is stored.
    • The Failure Records are updated after the first failure of each ignition cycle.