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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2004 🢒 GTO 🢒 Engine 🢒 Engine Controls - 5.7L 🢒 Scan Tool Output Controls

Scan Tool Output Control

Additional Menu Selection(s)

Description

A/C Clutch

Engine Output Controls

Activates the A/C compressor relay. The normal commanded state of the A/C relay is NONE. The relay status can also be monitored on the scan tool data parameter A/C Relay Command. The powertrain control module (PCM) will inhibit the operation of the A/C relay when the ambient air temperature is low enough to cause icing of the evaporator core.

Crankshaft Position Variation Learn

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Enables the powertrain control module (PCM) to learn the variations in the crankshaft position (CKP) system. The PCM will learn the variations once the following conditions are met:

    • Engine coolant temperature (ECT) is more than 70°C (159°F).
    • All instructions on the scan tool have been completed.
    • The accelerator pedal is smoothly applied until the fuel cut-OFF, as specified on the scan tool, is achieved, and then immediately released.

The PCM learns the variation values on the deceleration from fuel cut-OFF.

Cylinder Power Balance

Fuel System

Enables/Disables a cylinder by turning OFF the fuel injector to the cylinder. The fuel injector is normally enabled. The PCM disables the fuel injector when the following conditions are met:

    • All instruction on the scan tool are completed
    • Stabilized engine speed
    • The fuel injector is selected

When Disable is selected the PCM turns the injector OFF for 30 seconds. During this period, the engine operates with a misfire.

EVAP Purge Solenoid

Engine Output Controls / EVAP System

Activates the EVAP purge valve. The normal commanded state is NONE. The system will INCREASE or DECREASE the amount of EVAP purge valve opening by 5 percent increments within a range of 0 percent-100 percent. The system remains in the commanded state until cancelled by the tool or the fuel tank pressure (FTP) exceeds 24 mmHg (12 inH20).

EVAP Purge/Seal

Engine Output Controls / EVAP System

This control enables two 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 5 percent increments within a range of 0 percent-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 mmHg (12 inH20).

EVAP Vent Solenoid

Engine Output Controls / EVAP System

Activates the EVAP vent solenoid. The normal commanded state is NONE. When commanded ON, the vent valve 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 mmHg (12 inH20)

EVAP Test

Service Bay Tests

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 DTCs are set.

Fan Relay 1

Engine Output Controls / Fan Relays

Activates the cooling the fan 1 by enabling fan relay 1. The normal commanded state of the relay is NONE. The PCM allows relay control when the following conditions are met:

    • The transmission must be in Park or Neutral.
    • The A/C request is OFF.
    • The engine coolant temperature is less than 100°C (212°F).
    • No vehicle speed is detected

Fan Relay 2

Engine Output Controls / Fan Relays

Activates the cooling fan 2 by enabling fan relay 2. The normal commanded state of the relay is NONE. The PCM allows relay control when the following conditions are met:

    • The transmission must be in Park or Neutral.
    • The A/C request is OFF.
    • The engine coolant temperature is less than 100°C (212°F).
    • No vehicle speed is detected

Fuel Injector Balance

Fuel System

This function activates the selected fuel injector in order to verify the correct fuel injector flow. The ECM commands the fuel pump ON when the test is initiated and pulses the selected fuel injector on the second prompt. The normal commanded state is None. The scan tool initiates the test when the following conditions are met:

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

If any fuel injector needs to be tested again, the engine must be started and idled for 30 seconds.

Fuel Pump

Engine Output Controls

Controls the fuel pump relay. The normal commanded state is NONE. When commanded ON/OFF, the PCM turns the fuel pump ON/OFF. If the engine is running and the fuel pump is commanded OFF, the engine will stall. 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 of the fuel trim cells. When reset, fuel trim values will be set to zero percent.

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.

Malfunction Indicator Lamp

Engine Output Controls

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

O2S Heater Control

Engine Output Controls

Activates the HO2S Heater. The commanded states include None, ON, and OFF. The normal commanded state is None. On a cold engine, with the key ON, engine OFF, the HO2S signal will continue to drop below bias when commanded ON. The system remains in the commanded state until cancelled by the tool.

Oil Life Reset

Engine Output Controls

Allows the technician to reset the remaining engine oil life parameter. The current oil life value can be CLEARED, and a new value, between 0-100 percent, can be inserted with the numeric keys.

Request PCM/VCM Info. for SPS

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Allows a technician to program a control module through the data link connector (DLC). This procedure offers the ability to install software/calibrations matched to a particular vehicle. Follow Service Programming System (SPS) Procedures. Refer to in Vehicle Control Systems.

Request VDT Info. for SPS

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Allows a technician to program a control module through the data link connector (DLC). This procedure offers the ability to install software/calibrations matched to a particular vehicle. Follow Service Programming System (SPS) Procedures. Refer to in Vehicle Control Systems.

Reverse Inhibit*

Engine Output Controls

Enables the user to turn the reverse inhibit solenoid ON and OFF. The command grounds the reverse lockout solenoid control circuit.

RPM Control

IAC System

Activates the idle air control (IAC) valve 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 400-2,000 RPM. The set step value changes the RPM by increments of 25 RPM, 100-500 RPM. The system remains in the commanded state until cancelled by the tool.

Skip Shift Solenoid*

Engine Output Controls

Enables the technician to turn the skip shift solenoid ON and OFF. The command grounds the skip shift solenoid control circuit.

*Manual Transmission Only