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Diagnostic Trouble Code Type Definition

DIAGNOSTIC TROUBLE CODE (DTC) TYPE DEFINITIONS
DTCs are categorized by type. The type will indicate the action the DTC will take in storing a failure and illuminating the MIL.

When a Type A DTC diagnostic fails, the DTC is set immediately and the Malfunction Indicator Lamp (MIL) is illuminated. When a Type B DTC diagnostic fails, the Malfunction Indicator Lamp (MIL) will illuminate if the fault is present after two consecutive drive trips. When a Type C DTC diagnostic fails, the DTC will set immediately but will not illuminate the Malfunction Indicator Lamp (MIL). For some Type C DTCs only a message will appear on the Driver Information Center (DIC). Type C DTCs that DO NOT display a message were formerly referred to as Type D. For more information regarding DTC types refer to Powertrain Control Module Description and Operation.