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

Crank Request Signal

Engine Data 2

Yes/No

No

GEN L-Terminal Signal Command

Engine Data 2

On/Off

Off

Ignition 1 Signal

Engine Data 1

Volts

12.6 Volts

Starter Relay Command

Engine Data 2

On/Off

Off