Vehicle Control Module (VCM)

Diagnostic Chart:

DTC List

This information refers to domestic and Export calibration packages. Export vehicles may have differences in DTC types that will affect Malfunction Indicator Lamp (MIL) operation. Certain DTCs have been changed from type A to type C or, in some cases, type X. When a type A diagnostic fails, a 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. A type C DTC will set after one failure and be stored in history but will not illuminate the Malfunction Indicator Lamp (MIL). Type X DTCs have been turned off (the diagnostic does not run no codes are stored, and the Malfunction Indicator Lamp (MIL) will not illuminate.

If a system is malfunctioning and the associated DTC has been disabled (Type X), it may be beneficial to use the diagnostic table as a guide to aid in diagnosis. Many of the DTC Tables include a functional check of the system that may pinpoint a problem. However, it is important to remember that the DTC Tables are specifically designed for use only when a DTC is set. Therefore, a thorough understanding of the normal operation of the system being diagnosed is necessary and use of the tables for this purpose is at the discretion of the technician.

IMPORTANT: For Automatic Transmission DTC types, refer to Transmission.