GM Service Manual Online
For 1990-2009 cars only

Diagnostic Trouble Code (DTC) Identification Diagnostic Types

DTC

Description

DTC Type

Default Action

P0502

Vehicle Speed Sensor (VSS) Assembly Circuit Low Input

B

DTC P0502 will be stored in PCM history

P0719

TCC Brake Switch Circuit Low (Stuck ON)

D

DTC P0719 will be stored in PCM history

P0724

TCC Brake Switch Circuit High (Stuck OFF)

D

DTC P0724 will be stored in PCM history

P0742

Torque Converter Clutch (TCC) System Stuck ON

B

DTC P0742 will be stored in PCM history

P1870

Transmission Component Slipping

A

    • DTC P1870 will be stored in PCM history
    • The PCM will inhibit TCC engagement

DTC Types:

    • A - Emission related, will turn on the MIL after the first failure
    • B - Emission related, will turn on the MIL after two consecutive trips with a failure
    • C - Non-emission related, will turn on the service lamp after the first failure
    • D - Non-emission related, no lamps