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

Body Control Module (BCM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON, with the engine OFF. Transmission shift lever in the PARK position.

Battery 1

Ignition

Volts

0-25 V

Power Mode

Ignition

OFF/ACCY/RUN/CRANK

RUN

Engine Control Module (ECM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON, with the engine OFF. Transmission shift lever in the PARK position.

Battery 1

TCM

Volts

0-25 V

Command Gear

TCM

Park/Rev/Neu/4/3/2/1

Park

TCC Brake Switch

TCM

ON/OFF

OFF