GM Service Manual Online
For 1990-2009 cars only
Table 1: Powertrain Control Module (PCM) 6.6 Liter LB7
Table 2: Powertrain Control Module (PCM) 7.8 Liter LG4
Table 3: Powertrain Control Module (PCM) 8.1 Liter L18

Powertrain Control Module (PCM) 6.6 Liter LB7

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Ignition Switch in RUN/Engine running/Transmission in NEUTRAL/Air Conditioner is OFF

Low Coolant Level

Engine Data 1

Yes/No

No

ECT Sensor

Engine Data 1

Fuel System

°C/°F

Varies

Powertrain Control Module (PCM) 7.8 Liter LG4

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Ignition Switch in RUN/Engine Running/Transmission in NEUTRAL/Air Conditioner is OFF

Coolant Level Switch

Engine Data 2

Yes/No

No

ECT Sensor

Engine Data 1

Engine Data 2

°C/°F

Varies

Powertrain Control Module (PCM) 8.1 Liter L18

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Ignition Switch in RUN/Engine running/Transmission in NEUTRAL/Air Conditioner is OFF

Coolant Level Switch

Engine Data 2

Yes/No

No

ECT Sensor

Engine Data 1

Engine Data 2

EGR Data

°C/°F

Varies

Reduced Engine Power

Engine Data 1

Engine Data 2

EGR Data

On/Off

Off