GM Service Manual Online
For 1990-2009 cars only

Data List

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Ignition ON, Engine OFF, Transmission in Neutral or Park, Transfer Case in 2WD, and Brake Unapplied

4WD Status

4WAL 3-Sensor

2WD/4WD

2WD

ABS Lamp Command

4WAL 3-Sensor

On/Off

Off

ABS Pump Motor

4WAL 3-Sensor

On/Off

Off

ABS Stop State

4WAL 3-Sensor

On/Off

Off

ABS Relay Command

4WAL 3-Sensor

On/Off

Off

Brake Switch Status

4WAL 3-Sensor

On/Off

Off

Brake Warning Lamp Cmd

4WAL 3-Sensor

On/Off

Off

Diff. Pressure/Fluid Level Switch

4WAL 3-Sensor

Ok / Low

Ok

DRP Active

4WAL 3-Sensor

Yes/No

No

LF Dump Valve Command

4WAL 3-Sensor

On/Off

Off

LF Dump Valve Feedback

4WAL 3-Sensor

On/Off

Off

LF ISO Valve Command

4WAL 3-Sensor

On/Off

Off

LF ISO Valve Feedback

4WAL 3-Sensor

On/Off

Off

Left Front Wheel Speed

4WAL 3-Sensor

mph/km/h

3 km/h

Rear Dump Valve Command

4WAL 3-Sensor

On/Off

Off

Rear Dump Valve Feedback

4WAL 3-Sensor

On/Off

Off

Rear ISO Valve Command

4WAL 3-Sensor

On/Off

Off

Rear ISO Valve Feedback

4WAL 3-Sensor

On/Off

Off

Rear Wheel Speed

4WAL 3-Sensor

mph/km/h

3 km/h

RF Dump Valve Command

4WAL 3-Sensor

On/Off

Off

RF Dump Valve Feedback

4WAL 3-Sensor

On/Off

Off

RF ISO Valve Command

4WAL 3-Sensor

On/Off

Off

RF ISO Valve Feedback

4WAL 3-Sensor

On/Off

Off

Right Front Wheel Speed

4WAL 3-Sensor

mph/km/h

3 km/h