GM Service Manual Online
For 1990-2009 cars only
Table 1: LZ4, LZ9 Engine Control Module (ECM)
Table 2: LY7 Engine Control Module (ECM)
Table 3: Instrument Panel Cluster (IPC)

LZ4, LZ9 Engine Control Module (ECM)

Scan Tool Output Control

Additional Menu Selection(s)

Description

GEN L-Terminal

ECM, Special Functions, Output Control

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

Malfunction Indicator Lamp

ECM, Special Functions, Output Control

The instrument panel cluster (IPC) illuminates the malfunction indicator lamp (MIL) to test for an inoperative indicator.

Starter Relay

ECM, Special Functions, Output Control

The ECM commands the starter relay ON and OFF.

LY7 Engine Control Module (ECM)

Scan Tool Output Control

Additional Menu Selection(s)

Description

GEN L-Terminal

ECM, Special Functions, Output Control

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

Malfunction Indicator Lamp

ECM, Special Functions, Output Control

The instrument panel cluster (IPC) illuminates the malfunction indicator lamp (MIL) to test for an inoperative indicator.

Instrument Panel Cluster (IPC)

Scan Tool Output Control

Additional Menu Selection(s)

Description

Segment Check

IPC, Special Functions

The instrument panel cluster (IPC) illuminates all of the indicators for 7 seconds when On is selected.