GM Service Manual Online
For 1990-2009 cars only
Table 1: Body Control Module (BCM)
Table 2: Driver Door Module (DDM)
Table 3: HVAC
Table 4: Instrument Panel Controller (IPC)

Body Control Module (BCM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON Engine OFF/Doors, Trunk and Hood Closed/No Switches ON/Vehicle in PARK or NEUTRAL

ALC Switch

Exterior Lamps

Off/On

Varies with light level

Backup Lamp Relay Command

Exterior Lamps

Off/On

Off

BPP Sensor

Exterior Lamps

Volts

Varies

BPP Sensor Learn Home Position

Exterior Lamps

Counts

Varies

BPP Sensor Learn in Progress

Exterior Lamps

No/Yes

No

BPP Sensor High During Learn

Exterior Lamps

No/Yes

No

BPP Sensor Low During Learn

Exterior Lamps

No/Yes

No

BPP Sensor Move During Learn

Exterior Lamps

No/Yes

No

BPP Sensor Reference Signal

Exterior Lamps

Volts

5 volts

BPP Sensor Status Unlearned

Exterior Lamps

No/Yes

No

Day/Night Status

Exterior Lamps

Day/Night

Varies with light level

DRL Status

Exterior Lamps

Off/On

Varies with light level

Flash to Pass Switch

Exterior Lamps

Inactive/Active

Inactive

Fog Lamp Relay CMD

Exterior Lamps

Off/On

Off

Front Fog Lamp Switch

Exterior Lamps

Inactive/Active

Inactive

Hazard Lamp Switch

Exterior Lamps

Inactive/Active

Inactive

Headlamps OFF Switch

Exterior Lamps

Off/On

On

Headlamps ON Switch

Exterior Lamps

Inactive/Active

Inactive

High Beam Relay Command

Exterior Lamps

Off/On

Off

High Beam Select Switch

Exterior Lamps

Inactive/Active

Inactive

IGN Mode Sw Dimming CMD

Interior Lamps

Off/On

Off

Inadvert Power CMD

Interior Lamps

Off/On

Off

Inadvert Power Signal

Interior Lamps

Inactive/Active

Inactive

Left Turn Signal Switch

Exterior Lamps

Inactive/Active

Inactive

LF Door Ajar Switch

Interior Lamps

Closed/Open

Closed

LF Turn/Hazard Lamp Com

Exterior Lamps

Off/On

Off

LF Turn Lamp/DRL Status

Exterior Lamps

Off/On

Off

Low Beam Relay Command

Exterior Lamps

Off/On

Off

LR Turn/Hazard Lamp Com

Exterior Lamps

Off/On

Off

LR Turn Lamp/DRL Status

Exterior Lamps

Off/On

Off

Park Lamp Relay CMD

Exterior Lamps

Off/On

Off

Park Lamp Switch

Exterior Lamps

Off/On

Off

Rear Fog Lamp Relay CMD

Exterior Lamps

Off/On

Off

Rear Fog Lamp Switch

Exterior Lamps

Inactive/Active

Inactive

RF Door Ajar Switch

Interior Lamps

Closed/Open

Closed

RF Turn/Hazard Lamp Com

Exterior Lamps

Off/On

Off

RF Turn Lamp/DRL Status

Exterior Lamps

Off/On

Off

Right Turn Signal Switch

Exterior Lamps

Inactive/Active

Inactive

RR Turn/Hazard Lamp Com

Exterior Lamps

Off/On

Off

RR Turn Lamp/DRL Status

Exterior Lamps

Off/On

Off

Stop Lamp Relay Command

Exterior Lamps

Off/On

Off

Stop Lamp Status

Exterior Lamps

Off/On

Off

Theater Dimming Command

Interior Lamps

Off/On

Off

Trunk Release Switch

Interior Lamps

Inactive/Active

Inactive

Driver Door Module (DDM)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON Engine OFF/Doors, Trunk and Hood Closed/No Switches ON/Vehicle in PARK or NEUTRAL

Door Switch Backlight

Data

0%

0%

Exterior Courtesy Lamp

Data

Off/On

Off

HVAC

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON Engine OFF/Doors, Trunk and Hood Closed/No Switches ON/Vehicle in PARK or NEUTRAL

Ambient Light Sensor

Data

Counts

Varies

Instrument Panel Controller (IPC)

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Operating Conditions: Ignition ON Engine OFF/Doors, Trunk and Hood Closed/No Switches ON/Vehicle in PARK or NEUTRAL

Dim Down Switch

Data

Inactive/Active

Inactive

Dim Up Switch

Data

Inactive/Active

Inactive

Dome Lamp Switch

Data

Off/On

Off

Front Fog Indicator Com

Data

Off/On

Off

High Beam Indicator Com

Data

Off/On

Off

Left Turn Signal

Data

Off/On

Off

Park Lamps Signal

Data

Off/On

Off

Rear Fog Indicator Com

Data

Off/On

Off

Right Turn Signal

Data

Off/On

Off