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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.

Data

Ambient Light Sensor: The scan tool displays inactive or active. When the ambient light sensor detects day light conditions, the scan tool will display inactive. When the ambient light sensor detects low light conditions, the scan tool will display active.

Dimming Switch: The scan tool displays 0.0 to 16.0 volts, depending on the Dimming switch position.

Inputs

Courtesy Lamp Switch: The scan tool displays Inactive/Active. The input of the courtesy lamp switch is displayed as Active when the courtesy lamps are on.

Fog Lamp Switch: The scan tool displays Inactive/Active. The input of the fog lamp switch is displayed as active if the fog lamp switch is turned on.

Headlamp Switch: The scan tool displays Inactive/Active. The input of the headlamp switch is displayed as active when the headlamps switch is On.

Hi Beam On Switch: The scan tool displays Inactive/Active. The input of the high beam switch is displayed as active when the high beam headlamps are turned on.

Park Brake Switch: The scan tool displays inactive or active. When the park brake is Off, the scan tool will display inactive. When the park brake is applied, the scan tool will display active.

Park Lamp Switch: The scan tool displays On/Off. The input of the park lamp switch is displayed as On when the park lamps are command On.

Surveillance Mode Switch: The scan tool displays Inactive/Active. The input of the emergency vehicle interior lamp switch is displayed as active if the switch is turned to the off position.

Theater Dim 1 Ground: The scan tool displays Inactive/Active. The input of the theater dim 1 ground is displayed as active when the ground is present at the BCM for the theater dim lamps.

Theater Dim 2 Ground: The scan tool displays Inactive/Active. The input of the theater dim 2 ground is displayed as active when the ground is present at the BCM for the theater dim lamps.

Outputs

Ambient Light Sensor Relay: The scan tool displays On/Off. This output of the BCM is displayed as On when the ambient light sensor voltage reference output is present.

Backup Lamp Relay: The scan tool displays Inactive/Active. This output of the BCM is displayed as Active, if the BCM commands the backup lamps on.

DRL Relay: The scan tool displays On/Off. This output of the BCM is displayed as On, if the BCM commands the DRL lamps On.

Fog Lamp Relay: The scan tool displays On/Off. This output of the BCM is displayed as On, if the BCM commands the fog lamps on.

Headlamp Relay: The scan tool displays On/Off. This output of the BCM is displayed as On, if the headlamps are turned on.

Inadvertent Power Relay: The scan tool displays Off or On. When the BCM is not commanding the inadvertent power relay On, the scan tool will display Off. When the BCM is commanding the inadvertent power relay On, the scan tool will display On.

Park Lamp Relay: The scan tool displays On/Off. This output of the BCM is displayed as On, if the BCM commands the park lamps On.

Theater Dimming: The scan tool displays On/Off. This output of the BCM is displayed as On when the courtesy lamps are turned on.