GM Service Manual Online
For 1990-2009 cars only
Table 1: Engine Control Module (ECM)
Table 2: IPC

Engine Control Module (ECM)

Scan Tool Output Control

Additional Menu Selection(s)

Description

GEN L-Terminal

Engine Output Controls

The engine control module (ECM) commands the generator OFF by removing the 5-volt reference signal from the L terminal of the voltage regulator when you select OFF. The generator will then stop generating an output voltage.

IPC

Scan Tool Output Control

Additional Menu Selection(s)

Description

Lamp and Gauge Check

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The IPC illuminates the following indicators when you select ON:

    • ABS
    • Air Bag
    • BRAKE
    • Charge
    • Change Engine Oil
    • DRL
    • Engine Coolant Temperature
    • Fasten Safety Belt
    • High Beam
    • Liftgate Ajar
    • Low Fuel
    • Low Oil Pressure
    • Low Coolant Level
    • LOW Traction
    • Malfunction Indicator Lamp
    • Reduced Power (L61)
    • Security
    • Service Engine Soon
    • Traction Off
    • Upshift Indicator (manual transmission)

The IPC drives the following gages to maximum position when you select ON:

    • Engine Coolant Temperature Gage
    • Fuel Gage
    • Speedometer
    • Tachometer

The indicators should stay illuminated and all gages remain at maximum until commanded OFF. When commanded off, the indicators should turn off and all gages should remain at the minimum position until the test is exited or commanded ON.