GM Service Manual Online
For 1990-2009 cars only

Scan Tool Output Control

Additional Menu Selection(s)

Description

TCC Enable

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    • The PCM commands the TCC enable solenoid valve ON and OFF. The scan tool TCC Enable parameter should match the commanded state.
    • When the ignition is ON, and the engine is OFF, there are no limits to this control. The solenoid remains ON until commanded OFF, and vice versa. When the output control is exited, the solenoid state is determined by the PCM.
    • When the engine is running, the following control limits apply:
       - If the transmission range is Park or Neutral, the TCC enable solenoid may not be commanded OFF for more than a calibrated amount of time. If the solenoid is commanded OFF for a certain amount of time, the message "Engine running and TCC commanded off and off time exceeding acceptable time limit" appears on the scan tool display.
       - If the transmission range is Park or Neutral and the TCC control solenoid duty cycle is less than maximum capacity, the TCC enable solenoid may not be commanded ON. If the solenoid is requested ON during these conditions, the message "Engine running, enable solenoid on. Control solenoid not set to maximum capacity" appears on the scan tool display.
       - If the vehicle speed in third gear is greater than a calibrated value, the TCC enable solenoid may not be commanded OFF for more than a calibrated amount of time. If the solenoid is commanded OFF, and the vehicle speed is too high for a certain amount of time, the message "Engine running and TCC commanded off and off time exceeding acceptable time limit" appears on the scan tool display.
       - If the vehicle speed in third gear is greater than a calibrated value, and the TCC control solenoid duty cycle is less than maximum capacity, the TCC enable solenoid may not be commanded ON for more than a calibrated amount of time. If the solenoid is commanded ON during these conditions for a certain amount of time, the message "Engine running, enable solenoid on. Control solenoid not set to maximum capacity" appears on the scan tool display.