GM Service Manual Online
For 1990-2009 cars only
Table 1: Body Control Module Scan Tool Data Parameters
Table 2: Body Control Module Scan Tool Output Controls

Body Control Module Scan Tool Data Parameters

Parameter

System State

Expected Value

Definition

Operating Conditions: Engine ON

Accy/RAP Relay Command

--

On

The scan tool displays On or Off. This is the commanded state of the RAP relay. The scan tool displays ON when the BCM provides voltage to the RAP relay control circuit.

All Door Lock Cmd.

--

Off

The scan tool displays On or Off. This is the Lock output from the body control module (BCM) to all door lock actuators. When either door lock switch is operated to the Lock position the parameter is displayed as ON.

Ambient Light Sensor

--

Varies

This displays Volts. This is the current voltage at the ambient light sensor.

Ambient Light Status

--

Varies

The scan tool displays Night, Day, Unknown or Invalid. This is the state of the ambient light sensor.

Auto Hdlp. Disable Sw.

--

Inactive

The scan tool displays Active or Inactive. This is the state of the auto headlamp disable switch.

Backup Lamps

--

Off

The scan tool displays On or Off. This output of the BCM is displayed as ON when the backup lamps are turned ON.

Batt. Low at Start

--

No

The scan tool displays Yes or No. Yes is displayed if the state of the battery charge is low during cranking.

Batt. Open Ckt. Tested

--

No

The scan tool displays Yes or No.

Batt. Open Ckt. Voltage

--

Varies

This displays Volts. This is the voltage input to the BCM and is compared to the battery high resolution voltage for determining RVC charging voltage.

Batt. Voltage High Res.

--

Varies

This displays Volts. This is the voltage measured on a discreet high resolution voltage sense circuit to the BCM.

Battery Current

--

Varies

This displays amps. This parameter displays the information sent to the BCM from the battery current sensor to be used for determining RVC charging voltage.

Battery Sulfation Mode

--

Inactive

The scan tool displays Active or Inactive. The BCM will enter this mode when the interpreted generator output voltage is less than 13.2 volts for 45 minutes. In this mode the BCM will set a targeted output voltage of 13.8 volts for 5 minutes.

Battery Voltage

--

Varies

This displays Volts. This parameter displays the amount of battery voltage available to the body control module (BCM).

Battery Voltage

--

Normal

This displays Normal or Out of Range. This is the current state of the system voltage.

BPP Sensor

--

Varies

This displays Counts. This numeric value is the current brake pedal position.

BPP Sensor Reference

--

Varies

This displays Counts. This numeric value is the BPP sensor reference.

BPPS High During Learn

--

No

The scan tool displays Yes or No. If a short to battery positive voltage is detected in the stop lamp switch signal circuit during calibration, then the scan tool will display YES.

BPPS Learned Home Position

--

Varies

This displays Counts. This numeric value is the BPP sensor learned home position.

BPPS Low During Learn

--

No

The scan tool displays Yes or No. If a short to ground is detected in the stop lamp switch signal circuit during calibration, then the scan tool will display YES.

BPPS Move During Learn

--

No

The scan tool displays Yes or No. If the brake pedal is moved during calibration, the scan tool will display YES.

BPPS Status

--

Learned

The scan tool displays Invalid, Learned and Invalid, Undecided, Learning and Learned. This is the state of the BPPS calibration in the BCM.

Brake Applied Output Signal

--

Off

The scan tool displays On or Off. This output of the BCM is displayed as ON when the brake pedal is applied.

BTSI Fault

--

Not Present

The scan tool displays Present or Not Present. Present is displayed if the BCM senses a brake transmission shift interlock (BTSI) fault.

Calculated Brake Pedal Position

--

Varies

This displays Counts. This numeric value is the current brake pedal position.

Content Theft Mode

--

Varies

The scan tool displays True or False. This is the mode of the content theft system.

Courtesy Lamp PWM Cmd.

--

Varies

This displays percent. This is the current dimming percentage of the courtesy lamps.

Crank Abort

--

False

The scan tool displays True or False. This is the state of the crank abort.

Cruise Control Switch

--

Off

The scan tool displays Off, On, Resume, Set, Error or Cancel. This is the state of the cruise control switch as monitored by the body control module (BCM).

CTD Status

--

Disarmed

The scan tool displays Disarmed, Armed, Arm Delay or Alarm Active. The scan tool displays the current arming status of the content theft system.

CTD Trigger History 1-3

--

None

The scan tool displays None, Drvr. Door, Psgr. Door, LR Door, RR Door, Rear Closure, Mid Closure, Tonneau, Hood, Ignition, Intrusion, Inclination, Remote, Batt. Reconnect, Power Mode, Tamper, or Glass Break. The scan tool displays the input which previously caused a content theft alarm.

Ctsy. Lamp Actv. Reason

--

Varies

The scan tool displays Off, Panic, Manual, Air Bag, Door Open, RFA, RFA Theft, Door Closed, Exit or Manual Defeat. This is the reason for courtesy lamp activation.

Current CTD Trigger

--

None

The scan tool displays None, Drvr. Door, Psgr. Door, LR Door, RR Door, Rear Closure, Mid Closure, Tonneau, Hood, Ignition, Intrusion, Inclination, Remote, Batt. Reconnect, Power Mode, Tamper, or Glass Break. The scan tool displays the current input which has cause a content theft alarm.

Current Power Mode

--

Run

The scan tool displays Off, Accessory, Run or Crank Request. This parameter displays the power mode defined by the power mode master and communicated to the modules that require this information. This parameter should match the actual ignition switch position.

Desired Battery Voltage

--

Varies

This displays Volts. This is the desired battery voltage.

Dimming Control Reference

--

Varies

This displays Volts. This is the dimming control reference voltage.

Dimming Control Signal

--

Varies

This displays percent. This is the dimming control percentage.

Dimming Control Signal

--

Varies

This displays Volts. This is the dimming control signal voltage.

Door Key Cyl. Unlock Switch

--

Inactive

This displays Active or Inactive. The scan tool displays the current status of the door key cylinder unlock switch.

Door Lock Requestor

--

Varies

The scan tool displays Power Lock, Door Key Cyl., Rear Closure, Emergency, Keyless Entry, Passive Keyless, Remote, Delayed Lock, Relocking, Anti-Lockout, Exterior Sw. or Auto Locks. This is the current state of the door lock request as monitored by the BCM.

Driver Door Ajar Sw.

--

Door Closed

The scan tool displays Door Ajar or Door Closed. When the driver door is open or latched and not completely closed, the scan tool will display Door Ajar.

Driver Door Lock Sw.

--

Inactive

The scan tool displays Active or Inactive. This is the state of the driver door lock switch.

Driver Door Open Sw.

--

Closed

The scan tool displays Open or Closed. When the driver door is open, the scan tool will display Open.

Driver Door Unlock Sw.

--

Inactive

The scan tool displays Active or Inactive. This is the state of the driver door unlock switch.

Driver Identification

--

Varies

The scan tool displays Unknown or Driver 1-7. The scan tool displays the driver which has disarmed the content theft system.

DRL Relay Command

--

On

The scan tool displays On or Off. This output of the BCM is displayed as ON when the BCM turns ON the DRL lamps.

Drvr. Door Unlock Cmd.

--

Off

The scan tool displays On or Off. This is the state of the driver door unlock system.

Drvr. 1 RVS Status

--

Off

The scan tool displays On or Off. On is displayed if driver 1 has performed a remote vehicle start request.

Drvr. 2 RVS Status

--

Off

The scan tool displays On or Off. On is displayed if driver 2 has performed a remote vehicle start request.

Estimated Battery Temp.

--

Varies

This displays °C (°F). This is the current estimated battery temperature.

Flash to Pass Switch

--

Inactive

The scan tool displays Active or Inactive. When the multifunction switch is placed on the FTP position, the scan tool will display Active.

Front Fog Lamp Relay Command

--

Off

The scan tool displays On or Off. This output of the BCM is displayed as ON when the fog lamps are turned ON.

Front Fog Lamp Switch

--

Inactive

The scan tool displays Active or Inactive. When the fog lamp switch is placed in the ON position, the scan tool will display Active.

Fuel Economy Mode

--

Active

The scan tool displays Active or Inactive. This is the state of the fuel economy mode.

Hazard Lamp Switch

--

Inactive

The scan tool displays Active or Inactive. When the hazard switch is placed in the ON position, the scan tool will display Active.

Headlamp Switch

--

Inactive

The scan tool displays Active or Inactive. This is the state of the headlamp switch.

High Beam Relay Command

--

Off

The scan tool displays On or Off. This is the state of the high beam relay.

High Beam Select Switch

--

Inactive

The scan tool displays Active or Inactive. When the headlamp dimmer switch is placed in the HIGH position, the scan tool will display Active.

Hood Ajar Switch

--

Closed

The scan tool displays Ajar or Closed. When the hood is open or latched and not completely closed, the scan tool will display Ajar.

Hood Closed Switch

--

Active

The scan tool displays Active or Inactive. The scan tool displays the status of the hood closed portion of the hood ajar switch.

Hood Open Switch

--

Inactive

The scan tool displays Active or Inactive. The scan tool displays the status of the hood open portion of the hood ajar switch.

Hood Switch Fault

--

Not Present

The scan tool displays Present or Not Present. Present is displayed if the BCM senses a hood switch fault.

Horn Relay Command

--

Off

The scan tool displays On or Off. The horn output indicates the state that the control module has commanded for the relay.

HS Comm. Cmd.

--

Off

The scan tool displays On or Off. The scan tool displays the commanded state of the serial data communication enable circuit output. The scan tool displays ON when the BCM provides voltage to the circuit.

Idle Boost Level 2 Counter

--

Varies

This numeric value is the number of level  2 idle boosts requested by the RVC system to maintain proper battery charging at idle.

Idle Boost Level 3 Counter

--

Varies

This numeric value is the number of level  3 idle boosts requested by the RVC system to maintain proper battery charging at idle.

Ign. Off/Run/Crank

--

Run

The scan tool displays Key In/Off, Key Out/ACC, Crank or Run. The BCM uses this data input signal from the off/run/crank voltage circuits in order to determine the power mode (ignition switch position).

Ignition Accessory/Run

--

Active

The scan tool displays Active or Inactive. The BCM uses this data input signal from the accessory voltage circuits in order to determine the power mode (ignition switch position). Active is displayed when the ignition switch is in the Accy or Run positions.

Ignition Run/Crank

--

Active

The scan tool displays Active or Inactive. The BCM uses this data input signal from the ignition 1 voltage circuits in order to determine the power mode (ignition switch position). Active is displayed when the ignition switch is in the Run or Crank positions.

Ignition Switch Fault

--

No

The scan tool displays Yes or No. Yes is displayed if the BCM senses an ignition switch fault.

Incandescent Dimming PWM Cmd.

--

Varies

This displays percent. This is the current incandescent dimming percentage.

Int. Trunk/Liftglass Sw.

--

Inactive

The scan tool displays Active or Inactive. This is the state of the interior trunk or liftglass release switch.

Key Capture Solenoid Cmd.

--

Off

The scan tool displays On or Off. This is the state of the key capture solenoid.

Key in Ignition

--

Yes

The scan tool displays Yes or No. This is the state of the key in ignition.

Key in Ignition Status

--

Key In

The scan tool displays Key In or Key Out. The scan tool displays the ignition key in/out status.

LED Dimming PWM Cmd.

--

Varies

This displays percent. This is the current LED dimming percentage.

Left Rear Door Ajar Sw.

--

Door Closed

The scan tool displays Door Closed or Door Ajar. When the left rear door is open or latched and not completely closed, the scan tool will display Door Ajar.

Left Turn Signal Switch

--

Inactive

The scan tool displays Active or Inactive. When the turn signal switch is placed in the LEFT turn position, the scan tool will display Active.

LF Turn Signal

--

Off

The scan tool displays On or Off. This output of the BCM is displayed as ON when the left turn signal is turned ON.

Load Shed Lvl  2 Counter

--

Varies

This numeric value is the number of level 2 load sheds requested by the RVC system to maintain proper battery charging at idle.

Load Shed Lvl 3 Counter

--

Varies

This numeric value is the number of level 3 load sheds requested by the RVC system to maintain proper battery charging at idle.

Low Beam Relay Command

--

Off

The scan tool displays On or Off. This output of the BCM is displayed as ON when the low beam headlamps are turned ON.

LR Turn Signal

--

Off

The scan tool displays On or Off. This output of the BCM is displayed as ON when the left turn signal is turned ON or when the brakes are applied.

Off/Run/Crank Reference

--

Varies

This displays volts. This is the current off/run/crank reference voltage.

Off/Run/Crank Signal

--

Varies

This displays volts. This is the current off/run/crank signal voltage.

Parasitic Current

--

Varies

This displays amps. This is the state of the parasitic draw on the battery.

Park Brake Switch

--

Released

The scan tool displays Applied or Released. When the park brake is applied, the scan tool will display Applied.

Park Lamp Relay Cmd.

--

Off

The scan tool displays On or Off. This output of the BCM is displayed as ON when the park lamps are turned ON.

Parklamp Switch

--

Off

The scan tool displays On or Off. When the headlamp switch is in the PARK position, the scan tool will display ON.

Passenger Door Ajar Sw.

--

Door Closed

The scan tool displays Door Closed or Door Ajar. When the front passenger door is open or latched and not completely closed, the scan tool will display Door Ajar.

Passenger Door Open Sw.

--

Closed

The scan tool displays Open or Closed. When any passenger door other than the drivers door is open, the scan tool will display Open.

Powertrain HS Comm. Cmd.

--

Off

The scan tool displays On or Off. The scan tool displays the commanded state of the accessory wake up serial data circuit output. The scan tool displays ON when the BCM provides voltage to the circuit. This voltage output acts as a wake up signal for the powertrain control module(s).

Prev. State of Charge

--

Varies

The scan tool displays 0-100%. The scan tool displays the state of charge from the previous ignition off cycle.

Psgr. Door Lock Sw.

--

Inactive

The scan tool displays Active or Inactive. This is the state of the passenger door lock switch.

Psgr. Door Unlock Sw.

--

Inactive

The scan tool displays Active or Inactive. This is the state of the passenger door unlock switch.

Psgr. Door(s) Unlock Cmd.

--

Off

The scan tool displays On or Off. This is the state of the passenger doors unlock system.

Rear Closure Ajar Sw.

--

Inactive

The scan tool displays Active or Inactive. When the rear compartment is open or latched and not completely closed, the scan tool will display Active.

Regulator Setpoint

--

Varies

This displays percent. This is the set point of the voltage regulator as determined by the RVC system.

Remaining Starts 0

--

Varies

The scan tool displays True or False. True is displayed if there are no remaining starts.

Remote Start Attempts 0

--

Varies

The scan tool displays True or False. True is displayed if there are no remote start attempts.

RF Turn Signal

--

Off

The scan tool displays On or Off. This output of the BCM is displayed as ON when the right turn signal is turned ON.

Right Rear Door Ajar Sw.

--

Door Closed

The scan tool displays Door Closed or Door Ajar. When the right rear door is open or latched and not completely closed, the scan tool will display Door Ajar.

Right Turn Signal Switch

--

Inactive

The scan tool displays Active or Inactive. When the turn signal switch is placed in the RIGHT turn position, the scan tool will display Active.

RR Turn Signal

--

Off

The scan tool displays On or Off. This output of the BCM is displayed as ON when the right turn signal is turned ON or when the brakes are applied.

Run/Crank Relay Command

--

Off

The scan tool displays On or Off. The scan tool displays the commanded state of the run/crank relay. The scan tool displays ON when the BCM provides voltage to the run/crank relay control circuit.

Run Abort

--

False

The scan tool displays True or False. True is displayed if a run abort was executed.

Shift Lock Solenoid Command

--

Off

The scan tool displays On or Off. This is the state of the shift lock solenoid.

Start Up State of Charge

--

Varies

The scan tool displays 1-100%. The scan tool displays the state of charge at initial ignition ON cycle.

State of Charge

--

Varies

The scan tool displays 0-100%. The scan tool displays the present state of charge.

State of Charge Low

--

No

The scan tool displays YES/NO. The scan tool displays YES if the present state of charge is low.

Stop Lamp Relay Command

--

Off

The scan tool displays On or Off. This is the state of the stop lamp relay.

SWC Bank 1 Status

--

Idle

The scan tool displays Idle or Switch 1-10. This is the state of the steering wheel controls (SWC) bank 1.

Theft LED

--

Off

The scan tool displays On, Off, Flash Slow or Flash Fast. The scan tool displays the current status of the theft indicator as controlled by the CTD system.

Traction Control Switch

--

Inactive

The scan tool displays Active or Inactive. This is the state of the traction control switch.

Trunk Release Solenoid Command

--

Off

The scan tool displays On or Off.

Valet Switch

--

Inactive

The scan tool displays Active or Inactive. This is the state of the valet switch.

Washer Relay Cmd.

--

Off

The scan tool displays On or Off. When the windshield washer system is active, the scan tool displays the BCM the commanded output state of the windshield washer relay as On.

Windshield Washer Switch

--

Inactive

The scan tool displays Active or Inactive. When the washer switch is pressed, the scan tool displays the switch input to the BCM as Active. The BCM then commands the wiper relay ON and keeps it ON until 2 wipe cycles have completed after the switch has been released.

Windshield Wiper Switch

--

Off

The scan tool displays Off, Intermittent, Low, High or Switch Fault. When the windshield wiper system is active, the scan tool will display Intermittent or Low as selected. The scan tool will display Switch Fault if the BCM senses an invalid wiper switch input.

Wiper Delay Setting

--

Varies

This displays a numeric value. The scan tool displays 0/1-5. When the wiper switch is in the Delay mode, the scan tool will display the wiper switch delay position 1-5 as selected.

Wiper High Speed Relay Cmd.

--

Off

The scan tool displays On or Off. When the wiper system is in the active state, the scan tool displays the BCM commanded output to the wiper high relay as On.

Wiper High Speed Switch

--

Inactive

The scan tool displays Active or Inactive. When the wiper switch is in the high speed position, this parameter displays the switch input to the BCM as Active.

Wiper Park Switch

--

Inactive

The scan tool displays Active or Inactive. The body control module (BCM) uses this input to determine the position of the wipers. When the wipers are in the PARK or down position, the wiper motor park switch signal circuit of the BCM is pulled low and the scan tool will display Active.

Wiper Relay Cmd.

--

Off

The scan tool displays On or Off. When the windshield wiper system is active, the scan tool displays the BCM commanded output state of the wiper relay as On.

Body Control Module Scan Tool Output Controls

Scan Tool Output Control

Description

Accy/RAP Relay

This output control is used to command the Accy/RAP relay On and Off.

Backup Lamps

This output control is used to command the backup lamps On and Off.

BPP Sensor Calibration

This output control is used to command the BCM to calibrate the brake pedal position (BPP) sensor to zero.

Courtesy Lamp

This output control is used to command the foot wells and courtesy lamps On and Off.

Driver Door Unlock

The BCM momentarily pulses only the driver door lock motor. The driver door should unlock when ON is selected.

DRL

This output control is used to command the daytime running lamps On and Off.

Fog Lamps

This output control is used to command the fog lamps On and Off.

High Beams

This output control is used to command the high beam headlights On and Off.

Horn

This output control is used to command the horn On and Off.

Incandescent Dimming

The BCM dims the incandescent dimming from 0-100 percent when you select INCREASE or DECREASE by 20 percent increments.

LED Dimming

The BCM dims the LED dimming from 0-100 percent when you select INCREASE or DECREASE by 20 percent increments.

LF Turn Signal

This output control is used to command the left front turn signal On and Off.

Lock Rear Doors

This output control is used to command the rear doors to lock.

Low Beams

This output control is used to command the low beam headlights On and Off.

LR Turn Signal

This output control is used to command the left rear turn signal On and Off.

Parking Lamps

This output control is used to command the parking lamps On and Off.

RF Turn Signal

This output control is used to command the right front turn signal On and Off.

RR Turn Signal

This output control is used to command the right rear turn signal On and Off.

Run/Crank Relay

This output control is used to command the run/crank relay On and Off.

Setup SDM Primary Key in BCM

This output control is used to set up the SDM primary key into the BCM.

Shift Lock Solenoid

This output control is used to command the shift lock solenoid On and Off.

Trunk Release

This output control is used to command the trunk release solenoid On and Off.

Unlock Rear Doors

This output control is used to command the rear doors to unlock.

Wiper High Speed Relay

This output control is used to command the wiper high speed relay On and Off.

Wiper Relay

This output control is used to command the wiper relay On and Off.

Wiper Washer Motor

This output control is used to command the wiper washer motor On and Off.