GM Service Manual Online
For 1990-2009 cars only

Scan Tool Output Control

Additional Menu Selection(s)

Description

A/C Relay

Special Functions/Engine Output Controls

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the A/C compressor relay. When commanded ON, the A/C compressor will cycle ON/OFF for 3-5 seconds.

EGR Solenoid

Special Functions/Engine Output Controls

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the exhaust gas recirculation (EGR) solenoid. When commanded ON, the EGR solenoid will cycle from 0-100 percent for 3-5 seconds. This output can also be monitored on the scan tool by observing the EGR Position Sensor data parameter.

Engine Control Ignition Relay

Special Functions/Engine Output Controls

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the engine control ignition relay or MAIN relay. When commanded ON, the engine control ignition relay will cycle ON/OFF for 3-5 seconds.

EVAP Purge Solenoid

Special Functions/Engine Output Controls

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the evaporative emission (EVAP) purge solenoid. When commanded ON, the EVAP purge solenoid will cycle ON/OFF for 3-5 seconds. This output can also be monitored on the scan tool by observing the EVAP Purge Solenoid Command data parameter.

Fan High

Special functions/Engine Output Controls/Fan Controls

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the high speed cooling fan relay. When commanded ON, the cooling fan will turn ON at high speed for 5 seconds.

Fan Low

Special functions/Engine Output Controls/Fan Controls

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the low speed cooling fan relay. When commanded ON, the cooling fan will turn ON at low speed for 5 seconds.

Fuel Pump Relay

Special Functions/Engine Output Controls

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the fuel pump relay. When commanded ON, the fuel pump relay will cycle ON/OFF for 3-5 seconds.

IAC Motor Position - If Equipped

Special Functions/Engine Output Controls/IAC System

Important: This function is only allowed with the ignition ON, engine OFF.

This function activates the idle air control (IAC) valve to change position. The system will cycle the IAC valve for 3-5 seconds. This output can also be monitored on the scan tool data parameter IAC Position.

Idle Learn Reset

Special Functions/Engine Output Controls/Reset Learned Values

This function resets the base idle value learned by the engine control module (ECM).

ISC Actuator - If Equipped

Special Functions/Engine Output Controls

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the idle speed control (ISC) actuator. The ECM actuates the ISC actuator for 3-5 seconds when commanded ON. This output can also be monitored on the scan tool by observing the TP Sensor data parameter.

ISC System - If Equipped

Special Functions/Engine Output Controls/Reset Learned Values

This function resets the learned values for the idle speed control (ISC) system in the ECM.

Malfunction Indicator Lamp

Special Functions/Engine Output Controls

This function controls the malfunction indicator lamp (MIL). When commanded ON with the engine running, the ECM turns the (MIL) ON/OFF for 3-5 seconds. When commanded OFF with the ignition ON, engine OFF, the ECM turns the MIL ON/OFF for 3-5 seconds.

Reset ECM

Special Functions/Engine Output Controls/Reset Learned Values

This function resets all the values learned by the ECM.