GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2006 🢒 LaCrosse 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 Scan Tool Output Controls

Scan Tool Output Control

Additional Menu Selection(s)

Description

Camshaft Actuator

Special Functions/Engine Control Module/CMP Actuator System

This function controls the selected 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 40 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 1000-1400 RPM.

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

Camshaft Actuator Solenoid

Special Functions/Engine Control Module/CMP Actuator System

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

    • The ignition is ON with the engine OFF.
    • No engine speed is detected.

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

Cylinder Power Balance

Special Functions/Engine Control Module/Fuel System

Important: The Misfire Current and Misfire History parameters may not increment when using this function.

This function disables the selected fuel injector. The normal commanded state is None. The scan tool initiates the test when the following conditions are met:

    • The engine is operating and the engine idle is stable.
    • The vehicle speed is 0 km/h (0 mph).
    • There are no DTCs set for the vehicle speed sensor.

If the fuel injector was disabled for 30 seconds, fuel injector control is not allowed again on the same fuel injector for 60 seconds.

EC Ignition Relay

Special Functions/Engine Control Module/Output Controls

Important: The EC Ignition Relay Command parameter may not change states when using this output control.

This function controls the engine controls (EC) ignition or powertrain (PT) relay. The normal commanded state is NONE. The scan tool initiates the test when the following conditions are met:

    •  The engine is not running.
    •  There are no crankshaft/camshaft sensor DTCs set.
    •  The vehicle speed is zero.
    •  There are no vehicle speed sensor DTCs set.

When commanded ON/OFF, the ECM turns the EC ignition relay ON/OFF. The system remains in the commanded state until cancelled by the scan tool or the ECM detects an engine speed.

Engine Speed Control

Special Functions/Engine Control Module/TAC System

This function controls the idle speed override in 25 RPM, 100 RPM, and 500 RPM increments, from the base idle speed to 1400 RPM. The scan tool initiates the test when the following conditions are met:

    • The transmission is in Park or Neutral.
    • The engine speed is less than 1000 RPM

The engine speed will remain in the commanded state until cancelled by the scan tool.

EVAP Purge Solenoid

Special Functions/Engine Control Module/Output Controls/EVAP System

Important: The EVAP Purge Solenoid Command parameter may not change states when using this output control.

This function controls the 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 scan tool or the fuel tank pressure (FTP) sensor exceeds -30 mm Hg (-15 in H20).

EVAP Test

Service Bay Test

This function activates 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 have been completed.
    •  ECT is less than a specified value.
    • No EVAP DTCs are set.

EVAP Purge/Seal

Special Functions/Engine Control Module/Output Controls/EVAP System

Important: The EVAP Purge and Vent Solenoid Command parameters may not change states when using this output control.

This function activates both the EVAP purge solenoid valve and EVAP vent solenoid to seal the EVAP system. When activated, the purge valve is commanded to 0 percent and the vent valve is commanded ON, Not-venting. The normal commanded state for both solenoids is None. Both of the solenoids remain in the commanded state until cancelled by the scan tool or the fuel tank pressure (FTP) sensor exceeds -30 mm Hg (-15 in H20).

EVAP Vent Solenoid

Special Functions/Engine Control Module/Output Controls/EVAP System

Important: The EVAP Vent Solenoid Command parameter may not change states when using this output control.

This function controls the EVAP vent solenoid. The normal commanded state is NONE. When commanded ON, the vent valve switches to Not-venting. The system remains in the commanded state unless one of the following conditions occurs:

    • Cancelled by the scan tool
    • The EVAP canister Purge solenoid is more than 0 percent, and the fuel tank pressure (FTP) sensor exceeds -30  mm Hg (-15 in H20).

Fuel Injector Balance

Special Functions/Engine Control module/Fuel System

This function enables the fuel injector in order to verify the correct fuel injector flow. The ECM will pulse the selected fuel injector when the following conditions are met:

    • All instruction on the scan tool is complete.
    • A fuel injector is selected.
    • The ignition is ON with the engine OFF.

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

Fuel Pump

Special Functions/Engine Control Module/Output Controls

This function controls the fuel pump relay. The normal commanded state is NONE. The scan tool initiates the test when the following conditions are met:

    • There are no vehicle speed sensor DTCs set.
    • The vehicle speed is 0 km/h (0 mph).

When commanded ON/OFF, the ECM turns the fuel pump relay 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 for about 2 seconds or until cancelled by the scan tool or the ECM detects a vehicle speed.

Fuel Trim Reset

Special Functions//Engine Control Module/Fuel System

This function resets the fuel trim data and the learned values for the rear heated oxygen sensors.

Idle Learn Reset

Special Functions//Engine Control Module/TAC System

This function allows the throttle position and the idle speed to be relearned by the ECM, once the following conditions have been met.

    • The ignition is ON with the engine OFF.
    • The engine coolant temperature is between 5 - 85°C (41 - 185°F).
    • No TAC system DTCs are set.

Loop Status

Special Functions//Engine Control Module/Output Controls

This function controls the heated oxygen sensor (HO2S) loop status. The commanded states include NONE, OPEN, and CLOSED. The normal commanded state is NONE. The loop status changes as commanded, OPEN or CLOSED.

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

Malfunction Indicator Lamp

Special Functions//Engine Control Module/Output Controls

This function controls the malfunction indicator lamp (MIL). The normal commanded state is NONE. When commanded ON/OFF, the ECM turns the malfunction indicator lamp (MIL) ON/OFF. The system remains in the commanded state until cancelled by the scan tool.

Throttle Blade Control

Special Functions//Engine Control Module/TAC System

This function controls the throttle valve in 10 percent increments. The scan tool initiates the test when the following conditions are met:

    • There are no vehicle speed sensor DTCs set.
    • The vehicle speed is 0 km/h (0 mph).
    • The ignition is ON, with the engine OFF.
    • The ECM is not commanding a throttle learn.

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