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 OFF

Battery Voltage

BCM, Keyless Remote Start Data

Volts

12.6 Volts

Battery Voltage Signal

BCM, Power Mode

Volts

12.6 Volts

Power Mode

BCM, Power Mode

Off, Accessory, Run, Crank Request

Off

Run/Crank Relay

BCM, Keyless/Remote Start Data

On/Off

On

Run/Crank Relay Command

BCM, Power Mode

On/Off

On

LAT (2.4L) 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 L-Terminal Circuit Status

Electrical/Theft Data

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

OK

GEN L-Terminal Command

Electrical/Theft Data

%

0%

GEN F-Terminal Signal

Electrical/Theft Data

%

0%

Ignition 1 Signal

Electrical/Theft Data

Volts

12.6 V

PNP Switch

Electrical/Theft Data

Park / Neutral / In Gear

Park

Starter Relay Circuit Status

Electrical/Theft Data

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

OK

Starter Relay Command

Electrical/Theft Data

On/Off

Off

LZ4 (3.5L) 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 Circuit Status

Electrical/Theft Data

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

OK

GEN L-Terminal Command

Electrical/Theft Data

%

0%

Ignition 1 Signal

Electrical/Theft Data

Volts

12.6 Volts

PNP Switch

Electrical/Theft Data

Park / Neutral / In Gear

Park

Starter Relay Circuit Status

Electrical/Theft Data

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

OK

Starter Relay Command

Electrical/Theft Data

On/Off

Off

LY7 (3.6L) 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 Circuit Status

Electrical/Theft Data

Fault, Intermediate, OK

OK

GEN L-Terminal Signal Command

Electrical/Theft Data

ON / OFF

OFF

Ignition 1 Signal

Electrical/Theft Data

Volts

12.6 V

PNP Switch

Electrical/Theft Data

Park / Neutral / In Gear

Park

Starter Relay Command

Electrical/Theft Data

ON/OFF

OFF