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For 1990-2009 cars only

BCM Scan Tool Data Definitions

The BCM Scan Tool Data Definitions contains a brief description of all lighting system related BCM parameters available on the scan tool.

Brake Pedal Data List

BPPS High During Learn: The scan tool displays No or Yes. The scan tool displays Yes if signal is high during learn.

BPPS Learned Home Position: The scan tool displays voltage. The brake pedal position sensor learned home value of 0-5 volts.

BPPS Low During Learn: The scan tool displays No or Yes.

BPPS Move During Learn: The scan tool displays No or Yes.

BPP Sensor Circuit: The scan tool displays Inactive or Active. The commanded state of the brake pedal position sensor. When the brakes are applied the scan tool will display Active.

BPP Sensor: The scan tool displays Counts. With brake applied displays 1 to 3 counts. Unapplied displays 0.

BPP Sensor Reference: The scan tool displays Counts. Always displays 1 to 3 counts.

BPPS Status: The scan tool displays Unlearned/Learned/Invalid/Undecided. This is the status of the brake pedal position sensor with regards to learning the home position.

Brake Applied Output Signal: The scan tool displays On/OFF. When the brake is applied this parameter displays ON.

Calculated Brake Pedal Position: The scan tool displays counts. when the brake is applied displays 2 counts. When the brake is not applied displays 255 counts.

Exterior Lighting Data List

Ambient Light Sensor: The scan tool displays Volts. When the ambient light is high the voltage is high.

Ambient Light Status: The scan tool displays Night/Day/Unknown/Invalid.

Auto Hdlp. disable Sw.: The scan tool displays Inactive/Active. The scan tool only displays active when the switch in rotated and held in position. When the switch is rotated, the scan tool displays active for auto lts. ON and for auto lts. OFF.

Auto Hdlp. disable Sw.: The scan tool displays Inactive/Active.

Backup Lamps: The scan tool displays On/Off.

Brake Applied Output Signal: The scan tool displays On/Off. This output of the BCM is displayed as ON when the brake pedal is applied.

Flash to Pass Switch: The scan tool displays Inactive/Active. When the flash to pass switch is activated, the scan tool will display Active until the switch is released. Flash to pass does not operate if the head light switch is in the Auto, OFF or running lights only position.

Front Fog lamp Relay Command: The scan tool displays ON/OFF. When the fog lamp switch is placed in the ON position, the scan tool will display ON.

Front Fog Lamp Switch: The scan tool displays Inactive/Active. This output of the BCM is displayed as Active as long as the switch is pressed and held.

Hazard Lamp Switch:  The scan tool displays Inactive/Active. When the hazard switch is placed in the ON position, the scan tool will display Active.

Headlamp Switch: The scan tool displays Inactive/Active. When the headlamp switch is used to manually select head lights, the scan tool will display active.

High Beam Relay Command: The scan tool displays ON/OFF. When the dimmer switch is activated, the scan tool will display ON. Auto or manual lights must be on for this parameter.

High Beam Select Switch: The scan tool displays Inactive/Active. When dimmer switch is activated the scan tool displays active even if lights are not ON.

Left Cornering Lamp Command: The scan tool displays ON/OFF. When the turn signal switch is placed in the LEFT turn position, the scan tool will display ON. Head light switch auto position must be selected when viewing this parameter.

Left Turn Signal Switch: The scan tool displays Inactive/Active. When the turn signal switch is placed in the LEFT turn position, the scan tool will display Active.

LF Turn Signal: The scan tool displays ON/OFF. This output of the BCM constantly switches from ON to OFF as long as the left turn position is selected.

LR Turn Signal: The scan tool displays ON/OFF. This output of the BCM constantly switches from ON to OFF as long as the left turn position is selected.

Low Beam Relay Command: The scan tool displays ON/OFF. Displays ON when auto or manual head light switch positions are selected.

Park Lamp Relay Command: The scan tool displays ON/OFF. When the headlamp switch is in any position other than OFF the scan tool will display ON.

Park Lamp Switch: The scan tool display Inactive/Active. When the park brake is applied, the scan tool will display ON.

Right Cornering Lamp Command: The scan tool displays ON/OFF. When the turn signal switch is placed in the RIGHT turn position, the scan tool will display ON. Head light switch auto position must be selected when viewing this parameter.

Right Turn Signal Switch: The scan tool displays Inactive/Active. When the turn signal switch is placed in the RIGHT turn position, the scan tool will display Active.

RF Turn Signal: The scan tool displays ON/OFF. This output of the BCM constantly switches from ON to OFF as long as the right turn position is selected.

RR Turn Signal: The scan tool displays ON/OFF. This output of the BCM constantly switches from ON to OFF as long as the right turn position is selected.

Stop Lamp Relay Command: The scan tool displays ON/OFF. This output of the BCM is displayed as ON when the brakes are applied.

BCM Inputs Data List

Park Brake Switch: The scan tool displays Applied/Released. When the brake pedal is applied, the scan tool will display applied.

Valet Switch: The scan tool displays Inactive/Active. When activated displays Valet Mode on the uplevel radio, and display active on the scan tool.

Interior Lighting Data List

Courtesy Lamp PWM Command: The scan tool displays %. When the courtesy lamps are commanded ON the scan tool displays 99%. Commanded off displays 0%.

Courtesy Lamp Active Reason: The scan tool displays Manual/Door Open/OFF. When the courtesy lamp dimmer switch is manually truned on the scan tool displays Manual. When a door is open the scan tool displays door open.

Dimming Control Reference: The scan tool displays Voltage. Displays approximatly 3.2 volts.

Dimming Control Signal: The scan tool displays %. When the dimmer switch is manually rotated to the full dim position the scan tool will display 9%. When rotated to the full bright position the scan tool displays100%.

Dimming Control Signal: The scan tool displays volts. When the dimmer is rotated to full dim position the scan tool displays 2.9 volts. When rotated to full bright position the scan tool displays 3.19 volts.

Incandescent Dimming PWM Command: The scan tool displays %. When the incandescent lamps are placed in the full dim position the scan tool displays 10%. When placed in the full bright position the scan tool displays 94%. When commanded ON the scan tool displays 100%. When commanded Off displays 0%.

LED Dimming PWM Command: The scan tool displays %. When the LED lamps are placed in the full dim position the scan tool displays 5%. When placed in the full bright position the scan tool displays 96%. When commanded ON the scan tool displays 100%. When commanded Off displays 0%.

BCM Outputs Data List

Brake Applied Output Signal: The scan tool displays ON/OFF. This output of the BCM is displayed as ON when the brake pedal is applied.