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For 1990-2009 cars only

Powertrain Control Module Scan Tool Output Control

Scan Tool Output Control

Additional Menu Selection(s)

Description

Engine Controls Ignition Relay

Engine Output Controls

Enables or disables the Engine Controls Ignition Relay. The scan tool will command the engine controller to turn the relay ON or OFF. The normal commanded state is ON.

Engine Speed Control

TAC System

Activates the throttle activation control (TAC) system to change engine RPM. The normal commanded state is None. To enable the RPM control, all instruction on the scan tool must be completed. The system will increase or decrease the RPM within a range of 400-2,200 RPM. The set step value changes the RPM by increments of 25 RPM, 100 RPM, and 500 RPM. The system remains in the commanded state until cancelled by the scan tool.

EVAP Purge Solenoid

Engine Output Controls/EVAP System

Activates the purge solenoid in 10 percent increments from 0 to 100 percent. The device control will be aborted and inhibited if the fuel tank pressure (FTP) sensor exceeds 19 mm Hg (10 in H2O).

EVAP Vent Solenoid

Engine Output Controls/EVAP System

Activates the vent solenoid. The device control will be aborted and inhibited if the FTP sensor exceeds 19 mm Hg (10 in H2O).

EVAP Purge/Seal

Engine Output Controls/EVAP System

Simultaneously activates the purge solenoid in 10 percent increments from 0 to 100 percent and the vent solenoid. The device control will be aborted and inhibited if the FTP sensor exceeds 19 mm Hg (10 in H2O).

Exhaust CMP Actuator

CMP Actuator System

This function controls the exhaust camshaft position (CMP) actuator. The normal commanded state is 0 degrees. The system will INCREASE or DECREASE the exhaust camshaft timing by changing the duty cycle of the actuator in 5-degree increments up to 50 degrees. This also affects Desired Exh. CMP Angle Bank 1 and Bank 2.

Fuel Injector Balance

Fuel System

Enables the fuel injector in order to verify proper fuel injector flow. The PCM will pulse the selected injector when the following conditions are met:

    • All instruction on the scan tool completed.
    • Fuel injector selected
    • Key ON, engine OFF

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

Fuel Pump

Engine Output Controls

Activates the fuel pump relay for 2 seconds. Also turns fuel pump ON and OFF while engine is running.

Fuel Trim Enable

Fuel System

Disables the PCMs 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 scan tool.

Fuel Trim Reset

Fuel System

Activates the reset of fuel trim data in all fuel trim cells.

Idle Spark

Engine Output Controls/Spark Control

Enables or disables idle spark command. When commanded ON, the idle spark will be controlled to 13 degrees before top dead center. The normal commanded state is OFF.

Intake CMP Actuator

CMP Actuator System

This function controls the intake CMP actuator. The normal commanded state is 0 degrees. The system will INCREASE or DECREASE the intake camshaft timing by changing the duty cycle of the actuator in 5 degree increments up to 40 degrees. This also affects Desired Int. CMP Angle Bank 1 and Bank 2.

Loop Status

Engine Output Controls

Controls the system loop status. The commanded states include NONE, OPEN, or CLOSED. The normal commanded state is NONE. When commanded OPEN or CLOSED, the system remains in the commanded state until cancelled by the scan tool.

MIL

Engine Output Controls/Dash Lamps

Activates the malfunction indicator lamp (MIL). The MIL will remain illuminated until cancelled by the scan tool.

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Misfire Graphic

Graphs the accumulated misfires occurring in each cylinder. The scan tool allows for a reset of the misfire graph.

HO2S Heater Driver

Engine Output Controls

Activates the heated oxygen sensor (HO2S) heater. The commanded states include NONE, ON, and OFF. The normal commanded state is NONE. The system remains in the commanded state until cancelled by the tool.

Spark Retard

Engine Output Controls/Spark Control

Controls the amount of spark retard. The scan tool will command an increase or decrease in the amount of spark retard in 1-degree increments, within a range of 1-10 degrees. The degrees of spark retard will remain in the commanded state until cancelled by the scan tool. The normal commanded states is NONE.

Throttle Position

TAC System

Operates TAC motor in 10 percent increments to open or close the throttle blade. The test operates during key ON, engine OFF.

APP Learn

APP Learn

This procedure allows the TAC system to re-learn the minimum accelerator pedal position in the even of the bracket and rod assembly replacement.