GM Service Manual Online
For 1990-2009 cars only
Software Part Number: Part number of component program or the ECU. Used to determine applicability to vehicle RPO content.

Accessory 1: Input from ignition switch ACCESSORY circuit. Used to determine power mode. Hot in ACCESSORY and RUN.

Battery Power 2: Input showing the state of the Battery Power 2 circuit to the control module.

Battery Power 3: Input showing the state of the Battery Power 3 circuit to the control module.

Battery Voltage: The scan tool displays 0.0-16.0 volts. The battery voltage input represents the system voltage measured at the BCM ignition feed input.

Courtesy Ground: Input showing the state of the courtesy ground from the control module.

Crank: Input from ignition switch closed to B+ when the ignition switch is in the CRANK position.

Ground 2: Input showing the state of the Ground 2 circuit to the control module.

Ignition 0: Input to the control module from the ignition switch indicating the Ignition 0 position. Switch closed (HOT) in ignition switch positions Unlock, Accessory, Run, Crank

Ignition 1: Input to the control module from the ignition switch indicating the Ignition 1 position. Switch closed (HOT) in ignition switch positions Run, Crank

Key In Ignition: Input from ignition switch indicating that the ignition key is inserted into the ignition switch. HOT with key in ignition and ignition switch position LOCK.