GM Service Manual Online
For 1990-2009 cars only

Scan Tool Output Control

Additional Menu Selection(s)

Description

CAC Coolant Pump Relay Command

Output Controls

This function activates the charge air cooler (CAC) coolant pump relay. The normal commanded state is NONE. When commanded ON or OFF, the engine control module (ECM) turns the relay ON or OFF. The system remains in the commanded state until cancelled by the tool.

CMP Actuator Solenoid Exhaust - Bank 1

CMP Actuator System

This function controls the camshaft actuator solenoid exhaust-bank 1. The normal commanded state is NONE. The ECM turns the camshaft actuator solenoid ON/OFF when commanded ON/OFF. The scan tool initiates the test when the following conditions are met:

    • Turn the ignition to ON without the engine running.
    • The engine speed is not detected.
    • The system remains in the commanded state until cancelled by the tool

CMP Actuator Solenoid Exhaust - Bank 2

CMP Actuator System

This function controls the camshaft actuator solenoid exhaust-bank 2. The normal commanded state is NONE. The ECM turns the camshaft actuator solenoid ON/OFF when commanded ON/OFF. The scan tool initiates the test when the following conditions are met:

    • Turn the ignition to ON without the engine running.
    • The engine speed is not detected.

The system remains in the commanded state until cancelled by the tool.

CMP Actuator Solenoid Intake - Bank 1

CMP Actuator System

This function controls the camshaft actuator solenoid exhaust - bank 2. The normal commanded state is NONE. The ECM turns the camshaft actuator solenoid ON/OFF when commanded ON/OFF. The scan tool initiates the test when the following conditions are met:

    • Turn the ignition to ON without the engine running.
    • The engine speed is not detected.

The system remains in the commanded state until cancelled by the tool.

CMP Actuator Solenoid Intake - Bank 2

CMP Actuator System

This function controls the camshaft actuator solenoid intake - bank 2. The normal commanded state is NONE. The ECM turns the camshaft actuator solenoid ON/OFF, when commanded ON/OF. The scan tool initiates the test when the following conditions are met:

    • Turn the ignition to ON without the engine running.
    • The engine speed is not detected.

The system remains in the commanded state until cancelled by the tool.

Cylinder Power Balance

Fuel System

This function allows the control module to turn OFF individual fuel injectors. The fuel injector is normally enabled. The control module will disable the fuel injector under the following conditions:

    • All instructions on the scan tool are completed.
    • Engine speed is stable.
    • A fuel injector is selected by the technician on the scan tool.

When the DISABLE is selected, the control module will turn OFF the fuel injector for up to 30 seconds, or until commanded ENABLE with the can tool.

Engine Controls Ignition Relay

Output Controls

This function activates the engine control ignition relay. The normal commanded state is NONE. When commanded ON or OFF, the engine control module (ECM) turns the relay ON or OFF. The system remains in the commanded state until cancelled by the scan tool.

Engine Speed Control

TAC System

This function activates the throttle actuator control (TAC) system to change engine speed. The normal commanded state is NONE. Follow the scan tool instructions to enable RPM control. The system will increase or decrease the engine speed between 400 RPM and 2,200 RPM. The increments are 25, 100, and 500 RPM. The system remains in the commanded state until cancelled by the scan tool.

EVAP Purge Solenoid (PWM)

Output Controls/Evaporative Emissions (EVAP) System

This function activates the evaporative emission (EVAP) purge solenoid valve. The normal commanded state is NONE. The system will increase or decrease the amount of purge by changing the duty cycle of the purge valve in 10 percent increments within a range of 0-100 percent. The system remains in the commanded state until cancelled by the tool or the fuel tank pressure (FTP) exceeds -24 mm Hg (-12 in H20).

EVAP Purge/Seal

Output Controls/Evaporative Emissions (EVAP) System

This function activates 2 functions. One function increases or decreases the amount of purge by changing the duty cycle of the purge valve and commanding the vent ON, non-venting. The normal commanded state of both valves is NONE. The system will INCREASE or DECREASE the amount of EVAP purge valve opening by 10 percent increments within a range of 0-100 percent. The second function seals the system after using the purge function to obtain a specific amount of FTP. When activated, the purge valve is commanded to 0 percent and the vent valve is commanded ON, non-venting. Both functions remain in the commanded state until cancelled by the tool, or the FTP exceeds -24 mm Hg (-12 in H20).

Evaporative Emission Service Bay Test

Service Bay Test

Activate the Service Bay Test to verify the integrity of the EVAP system. The scan tool initiates the test when the following conditions are met:

    • All instructions on the scan tool is complete.
    • The engine coolant temperature is less than a specified value.
    • There are no DTCs set.

EVAP Vent Solenoid

Output Controls/Evaporative Emission (EVAP) System

This function controls the evaporative emission (EVAP) vent solenoid. The normal commanded state is NONE. When commanded ON, the vent solenoid switches to non-venting. The system remains in the commanded state unless one of the following conditions occurs:

    • Cancelled by the tool
    •  Purge is greater than 0 percent, and the FTP exceeds -24 mm Hg (-12 in H20)

Exhaust CMP Actuator - Bank 1

CMP Actuator System

This function controls the bank 1 exhaust camshaft actuator. The normal commanded state is NONE. The system will INCREASE or DECREASE the angle of the selected camshaft in 5-degree increments up to 25 crankshaft degrees. The scan tool initiates the test when the following conditions are met:

    • The vehicle speed is 0 km/h (0 mph)
    • The transmission is in Park or Neutral
    • The engine speed is between 1,000-1,400 RPM.
    • The system remains in the commanded state until cancelled by the tool.

Exhaust CMP Actuator - Bank 2

CMP Actuator System

This function controls the bank 2 exhaust camshaft actuator. The normal commanded state is NONE. The system will INCREASE or DECREASE the angle of the selected camshaft in 5-degree increments up to 25 crankshaft degrees. The scan tool initiates the test when the following conditions are met:

    • The vehicle speed is 0 km/h (0 mph)
    • The transmission is in Park or Neutral
    • The engine speed is between 1,000-1,400 RPM.
    • The system remains in the commanded state until cancelled by the tool.

Fuel Injector Balance

Fuel System

Enables fuel injector to verify proper fuel injector flow. The ECM also enables the fuel pump. The ECM will pulse the selected injector when the following conditions are met:

    • All instructions on the scan tool is complete.
    • Fuel injector selected
    • Ignition ON with the engine OFF.

The selected fuel injector can only be flowed/pulsed once per ignition cycle.

Fuel Pump Relay

Output Controls

This function activates the fuel pump relay. The normal commanded state is NONE. The ECM turns the fuel pump relay ON/OFF, when commanded ON/OFF. If the engine is running and the fuel pump relay is commanded OFF, the engine will stall. The system remains in the commanded state until cancelled by the tool.

Fuel Trim Enable

Fuel System

Disables the ECMs ability to learn new fuel trim parameters. The commanded states are NONE, ENABLED, DISABLED. The normal commanded state is NONE. The system remains in the commanded state until cancelled by the tool.

Fuel Trim Reset

Fuel System

This function activates the reset of fuel trim data in all fuel trim cells.

HO2S Bank 1 Sensor 1 Heater

Output Control/Heated Oxygen Sensors

Activate HO2S bank 1 sensor 2 heater. The ECM commands the heater ON in 10 percent increments from 0 to 100 percent. The normal commanded state is NONE. The system remains in the commanded state until cancelled by the tool.

HO2S Bank 1 Sensor 2 Heater

Output Control/Heated Oxygen sensors

Activate HO2S bank 1 sensor 2 heater. The ECM commands the heater ON in 10 percent increments from 0 to 100 percent. The normal commanded state is NONE. The system remains in the commanded state until cancelled by the tool.

HO2S Bank 2 Sensor 1 Heater

Output Control/Heated Oxygen sensors

Activate HO2S bank 1 sensor 2 heater. The ECM commands the heater ON in 10 percent increments from 0 to 100 percent. The normal commanded state is NONE. The system remains in the commanded state until cancelled by the tool.

HO2S Bank 2 Sensor 2 Heater

Output Control/Heated Oxygen Sensors

Activate HO2S bank 1 sensor 2 heater. The ECM commands the heater ON in 10 percent increments from 0 to 100 percent. The normal commanded state is NONE. The system remains in the commanded state until cancelled by the tool.

Idle Spark

Output Control/Ignition Control

Disable or enable idle spark before the engine running.

Intake CMP Actuator - Bank 1

CMP Actuator System

This function controls the intake CMP actuator - bank 1. The normal commanded state is NONE. The system will INCREASE or DECREASE the angle of the selected camshaft in 5 degree increments up to 20 crankshaft degrees. The scan tool initiates the test when the following conditions are met:

    • The vehicle speed is 0 km/h (0 mph).
    • The transmission is in Park or Neutral.
    • The engine speed is between 1,000-1,400 RPM.

The system remains in the commanded state until cancelled by the tool.

Intake CMP Actuator - Bank 2

CMP Actuator System

This function controls the intake camshaft actuator - bank 2. The normal commanded state is NONE. The system will increase or decrease the angle of the selected camshaft in 5 degree increments up to 20 crankshaft degrees. The scan tool initiates the test when the following conditions are met:

    • The vehicle speed is 0 km/h (0 mph).
    • The transmission is in Park or Neutral.
    • The engine speed is between 1,000-1,400 RPM.

The system remains in the commanded state until cancelled by the tool.

Loop Status

Output Controls

This function changes to loop status. The commanded states include Open and Closed. When commanded Open or Closed, the system remains in the commanded state until cancelled by the scan tool.

Malfunction Indicator Lamp (MIL)

Output Controls

This function activates the malfunction indicator lamp (MIL). The commanded states include NONE, ON and OFF. When commanded ON or OFF, the system remains in the commanded state until cancelled by the scan tool.

Misfire Graphic

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This function graphs the accumulation of misfires occurring in each cylinder. The system remains in the commanded state until cancelled by the scan tool.

O2S Heater Driver 1-4

Output Controls/Heated Oxygen Sensors

This function activates the oxygen sensor heater. The normal commanded state is NONE. The system will INCREASE or DECREASE the amount of current in 10 percent increments within a range of 0-100 percent. The system remains in the commanded state until cancelled by the tool.

Reset Idle Learn

TAC System

This functions allows the idle speed to be relearned by the control module.

SCB Solenoid

Output Controls

Enable solenoids, increase or decrease in 10 percent increments from NONE. The range is 0-100 percent.

Spark Retard

Spark Control

This function control the amount of spark retard by the control module. The normal commanded state is NONE. The System will increase or decrease the amount of spark retard from 1-10 degrees maximum retard. The system will remain in the commanded state until cancelled by the scan tool.

Throttle Positions

Output Controls/Throttle Actuator Control (TAC) System

This function opens the throttle plate in 25 percent increments.

The scan tool initiates the test when the following conditions are met:

    • Turn ON the ignition, with the engine OFF.
    • The vehicle speed is 0 km/h mph.

The system remains in the commanded state until cancelled by the scan tool.