GM Service Manual Online
For 1990-2009 cars only

Generator Battery Control Module (GBCM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions:  Ignition ON/Engine OFF

Battery Voltage Signal

Body, Generator Battery Control Module

Volts

12.3 V

Generator L Terminal Signal Command

Body, Generator Battery Control Module

Percent

0 Percent

Regulated Voltage Control Current Sensor

Body, Generator Battery Control Module

Amps

1 Amp

Running State of Charge

Body, Generator Battery Control Module

Percent

90 Percent

Powertrain Control Module (PCM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON/Engine OFF

Crank Request Signal

PCM, Data Display, Engine Data Display, Electrical/Theft Data

Yes/No

No

Generator L Terminal Signal Command

PCM, Data Display, Engine Data Display, Electrical/Theft Data

Off/On

Off

Generator F Terminal Signal

PCM, Data Display, Engine Data Display, Electrical/Theft Data

%

10-90%

Ignition 1 Signal

PCM, Data Display, Engine Data Display, Electrical/Theft Data

Volts

9.6-14.4 V

Starter Relay Circuit Status

PCM, Data Display, Engine Data Display, Electrical/Theft Data

Fault, Indeterminate, OK

OK

Starter Relay Command

PCM, Data Display, Engine Data Display, Electrical/Theft Data

Off/On

Off

TR Sw.

PCM, Transmission Data

Park, Reverse, Neutral, Drive 5, Drive 4, Drive 3, Drive 2, Drive 1

Park