GM Service Manual Online
For 1990-2009 cars only
Table 1: Engine Control Module (ECM)
Table 2: Powertrain Control Module (PCM)
Table 3: Instrument Panel Cluster (IPC)

Engine Control Module (ECM)

Scan Tool Output Control

Additional Menu Selection(s)

Description

GEN L-Terminal

Engine, Engine Electrical, Special Functions, ECM

The engine control module (ECM) commands the generator OFF when off is selected. The generator will then stop generating an output voltage.

Starting Relay Command

Engine, Engine Electrical, Special Functions, ECM

The ECM commands the starter relay ON and OFF.

Powertrain Control Module (PCM)

Scan Tool Output Control

Additional Menu Selection(s)

Description

GEN L-Terminal

Engine, Engine Electrical, Special Functions, PCM

The powertrain control module (PCM) commands the generator OFF when off is selected. The generator will then stop generating an output voltage.

Instrument Panel Cluster (IPC)

Scan Tool Output Control

Additional Menu Selection(s)

Description

Malfunction Indicator Lamp

Body and Accessories, Instrument Panel, Special Function, IPC

The instrument panel cluster (IPC) illuminates the malfunction indicator lamp (MIL) to test for an inoperative indicator. The battery indicator is just to the left of the engine indicator.