GM Service Manual Online
For 1990-2009 cars only

Scan Tool Output Control

Additional Menu Selection(s)

Description

Engine Output Controls

GEN L-Terminal

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

Engine Output Controls

Starter Relay Control

The ECM commands the Crank Relay OFF by removing the 12 volts from the control circuit of Crank Relay when you select OFF. Voltage will then stop flowing through the switch of the Crank Relay.