GM Service Manual Online
For 1990-2009 cars only

Body Control Module (BCM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON/Engine Running

Battery Low at Start

Data Display/ Charging Info

Yes/No

No

Batt. Open Ckt. Tested

Data Display/ Charging Info

Yes/No

No

Batt. Open Ckt. Voltage

Data Display/ Charging Info

Volts

13.03 Volts

Battery Voltage

Data Display/ Charging Info

Volts

13.9 Volts

Batt. Voltage High Res.

Data Display/ Charging Info

Volts

12.417 Volts

Parasitic Current

Data Display/ Charging Info

Amps

0.0 Amps

Prev. State of Charge

Data Display/ Charging Info

%

90%

Start Up State of Charge

Data Display/ Charging Info

%

80%

State of Charge

Data Display/ Charging Info

%

85%

State of Charge Low

Data Display/ Charging Info

Yes/No

No

Digital Radio Receiver (DRR)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON/Engine Running

Battery Voltage

Data Display

Volts

13.9 Volts

Engine Control Module (ECM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON/Engine OFF

Crank Request Signal

Electrical/Theft Data

Yes/No

No

GEN F-Terminal Signal

Electrical/Theft Data

%

0%

GEN L-Terminal Signal Command

Electrical/Theft Data

ON / OFF

OFF

GEN L-Terminal Circuit Status

Electrical/Theft Data

Incomplete/Short Gnd/Open/Short to B+/OK

OK

Ignition 1 Signal

Electrical/Theft Data

Volts

Varies

PNP Switch

Electrical/Theft Data

Park/Neutral/In Gear

Park

Starter Relay Command

Electrical/Theft Data

On/Off

Off

Starter Relay Circuit Status

Electrical/Theft Data

Incomplete/Short Gnd/Open/Short to B+/OK

OK

Instrument Panel Cluster (IPC)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON/Engine Running

Battery Voltage

Data Display

Volts

13.9 Volts

Vehicle Theft Deterrent (VTD)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON

Ignition Voltage Signal

Data Display

Present / Not Present

Present

Start Disabled

Data Display

Yes/No

No

Sensing Diagnostic Module (SDM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON/Engine Running

Battery Voltage Signal

Data Display

Volts

13.9 Volts

Transmission Control Module (TCM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON/Transmission in Park

IMS

Engine Electrical

Park, Park/Reverse, Reverse, Reverse/Neutral, Neutral, Neutral/Drive 4, Drive 4, Drive 4/Drive 3, Drive 3, Drive 3/Drive 2, Drive 2, Drive 2/Drive 1, Drive 1, INVALID, OPEN

Park