GM Service Manual Online
For 1990-2009 cars only

Powertrain Control Module (PCM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Ignition ON/Engine OFF

GEN F-Terminal Signal

Engine Data 2

%

0%

GEN L-Terminal Signal Command

Engine Data 2

On/Off

Off

Ignition 1 Signal

Engine Data 1, Engine Data 2

Volts

12.6 Volts

Transmission Control Module (TCM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Ignition ON/Engine OFF

TR Sw.

Engine Data 2

Park, Reverse, Neutral, Drive 4, Drive 3, Drive 2, Drive 1

Park