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HOMESERVICE MANUALSCHEVROLET2003AVALANCHE 1500 2WD V8-5.3L VIN TREPAIR AND DIAGNOSISLIGHTING AND HORNSTESTING AND INSPECTIONSCAN TOOL TESTING AND PROCEDURESSCAN TOOL DATA DEFINITIONS
2003 Chevrolet Avalanche 1500 2WD V8-5.3L VIN T
Scan Tool Data Definitions
2003 Chevrolet Avalanche 1500 2WD V8-5.3L VIN TSECTION Scan Tool Data Definitions
DATA
Backlight Dimming: The scan tool displays the duty cycle of the pulse width modulated (PWM) signal distributed by the BCM to the PWM controlled I/P backlighting based on the position of the I/P dimmer switch, thumbwheel. The scan tool displays 0 percent when the headlamp switch is in the AUTO position and the daytime running lamps (DRL) are ON or the I/P dimmer switch is in the FULL DIM position. The scan tool displays approximately 85 percent when either the low beam headlamps or park lamps are activated and the I/P dimmer switch is in the FULL BRIGHT position.
Battery Voltage: The scan tool displays the battery system voltage received by the module.
Dimming Input: The scan tool displays the voltage value indicating the position of the I/P dimmer switch, thumbwheel. The scan tool displays 4 volts when the headlamp switch is in the AUTO position and the daytime running lamps (DRL) are ON or the I/P dimmer switch is in the FULL DIM position. The scan tool displays 0 volts when either the park lamps or the headlamps are turned ON and the I/P dimmer switch is in the FULL BRIGHT position.
Dimming Level: The scan tool displays the duty cycle of the pulse width modulated (PWM) signal distributed by the BCM to the interior lighting circuits. The scan tool displays 0 percent when the interior lamps illumination is OFF. The scan tool displays 100 percent when the interior lamp illumination is at full intensity.
Indicator Dimming: The scan tool displays the duty cycle of the pulse width modulated (PWM) signal distributed by the BCM to the PWM controlled I/P backlighting based on the position of the I/P dimmer switch, thumbwheel. The scan tool displays 1.2 percent when the headlamp switch is in the AUTO position and the daytime running lamps (DRL) are ON or the I/P dimmer switch is in the FULL DIM position. The scan tool displays 100 percent when either the headlamps or park lamps are activated and the I/P dimmer switch is in the FULL BRIGHT position.
Light Sensor: The scan tool displays the output voltage of the ambient light sensor based on the intensity of light detected. As the light intensity increases, the sensor displayed voltage decreases. In the LIGHT state, a low voltage, not less than 1.75 volts, is present and the DRL will be ON. In the DARK state, a high voltage, up to 4.9 volts, is present and the headlamps will be ON.
INPUTS
Courtesy Lamp Switch: The scan tool displays the position of the courtesy lamp switch. The scan tool displays Active when the switch is turned ON. The BCM uses this data in controlling the operation of the courtesy lamps.
Front Fog Lamp Switch: The scan tool the front fog lamp switch. The scan tool displays ACTIVE or INACTIVE when the switch is depressed. The BCM uses this data in controlling the operation of the front fog lamps.
Flash to Pass Switch: The scan tool displays the position of the flash to pass switch. The scan tool displays On when the switch is pulled to activate the high beams momentarily while the switch is held.
Headlamp Switch: The scan tool displays the position of the headlamp switch. The scan tool displays Active when the headlamp switch is in the ON position. The BCM uses this data in controlling the operation of the headlamps.
High Beam Switch: The scan tool displays the position of the high beam switch. The scan tool displays On when the switch is used to activate the high beams.
Ignition 0: The scan tool displays the position of the ignition switch. The scan tool displays On when the ignition switch is in the RUN or CRANK position.
Ignition 1: The scan tool displays the position of the ignition switch. The scan tool displays On when the ignition switch is in the RUN or CRANK position.
Ignition Accessory: The scan tool displays the position of the ignition switch. The scan tool displays On when the ignition switch is in the ACCY position only.
Inadvertent Power Relay: The scan tool displays the state of the inadvertent power battery rundown protection feature of the BCM. The scan tool displays Off when all inadvertent power circuits are functioning normally.
Interior Lamp Defeat Switch: The scan tool displays the position of the courtesy/dome lamp override switch. The scan tool displays On when the switch is activated requesting the BCM to override the normal interior lamp activation inputs and deactivate the interior lighting.
Key in Ignition: The scan tool displays Yes when the key has been inserted into the ignition switch. The scan tool displays No after the key has been removed.
Park Brake Switch: The scan tool displays the position of the park brake pedal. The scan tool displays Set when the park brake is engaged closing the switch. The BCM uses this data in controlling the operation of the park brake indicator, the reminder chime feature and the DRL system.
Park Lamp Switch: The scan tool displays the position of the park lamp switch. The scan tool displays ON when the park lamp switch is in the ON position. The BCM uses this data in controlling the operation of the park lamps.
OUTPUTS
High Beams: The scan tool displays the commanded state of the high beam relay. The scan tool displays On when the BCM allows the high beam relay to go to ground activating the high beam headlamps.
Low Beams: The scan tool displays the commanded state of the low beam relay. The scan tool displays ON when the BCM allows the high beam relay to go to activate the low beam headlamps.
Park Lamp Relay: The scan tool displays the commanded state of the park lamp relay. The scan tool displays ON when the BCM allows the park lamp relay to activate the park lamps.
Dimming Level: The scan tool displays the commanded state of the interior dimmable lamps. The scan tool displays a percentage based on the position of the thumb wheel.
Daytime Running Lamps: The scan tool displays the commanded state of the daytime running lamps (DRL). The scan tool displays ON when the BCM allows the DRL relay to activate the DRL.
OUTPUT CONTROL
Dimming Level: The scan tool displays the duty cycle of the pulse width modulated (PWM) signal distributed by the BCM to the interior lighting circuits. The scan tool displays 0 percent when the interior lamps illumination is OFF. The scan tool displays 100 percent when the interior lamp illumination is at full intensity.
Daytime Running Lamps: The scan tool displays the commanded state of the daytime running lamps (DRL). The scan tool displays On when the BCM illuminates the DRL.
Park Lamp Relay: The scan tool displays the commanded state of the park lamp relay. The scan tool displays On when the BCM allows the park lamp relay to go to ground to activate the park lamps.
Backlight Dimming: The scan tool displays the duty cycle of the pulse width modulated (PWM) signal distributed by the BCM to the PWM controlled I/P backlighting based on the position of the I/P dimmer switch, thumbwheel. The scan tool displays 0 percent when the headlamp switch is in the AUTO position and the daytime running lamps (DRL) are ON or the I/P dimmer switch is in the FULL DIM position. The scan tool displays approximately 85 percent when either the low beam headlamps or park lamps are activated and the I/P dimmer switch is in the FULL BRIGHT position.
Battery Voltage: The scan tool displays the battery system voltage received by the module.
Dimming Input: The scan tool displays the voltage value indicating the position of the I/P dimmer switch, thumbwheel. The scan tool displays 4 volts when the headlamp switch is in the AUTO position and the daytime running lamps (DRL) are ON or the I/P dimmer switch is in the FULL DIM position. The scan tool displays 0 volts when either the park lamps or the headlamps are turned ON and the I/P dimmer switch is in the FULL BRIGHT position.
Dimming Level: The scan tool displays the duty cycle of the pulse width modulated (PWM) signal distributed by the BCM to the interior lighting circuits. The scan tool displays 0 percent when the interior lamps illumination is OFF. The scan tool displays 100 percent when the interior lamp illumination is at full intensity.
Indicator Dimming: The scan tool displays the duty cycle of the pulse width modulated (PWM) signal distributed by the BCM to the PWM controlled I/P backlighting based on the position of the I/P dimmer switch, thumbwheel. The scan tool displays 1.2 percent when the headlamp switch is in the AUTO position and the daytime running lamps (DRL) are ON or the I/P dimmer switch is in the FULL DIM position. The scan tool displays 100 percent when either the headlamps or park lamps are activated and the I/P dimmer switch is in the FULL BRIGHT position.
Light Sensor: The scan tool displays the output voltage of the ambient light sensor based on the intensity of light detected. As the light intensity increases, the sensor displayed voltage decreases. In the LIGHT state, a low voltage, not less than 1.75 volts, is present and the DRL will be ON. In the DARK state, a high voltage, up to 4.9 volts, is present and the headlamps will be ON.
INPUTS
Courtesy Lamp Switch: The scan tool displays the position of the courtesy lamp switch. The scan tool displays Active when the switch is turned ON. The BCM uses this data in controlling the operation of the courtesy lamps.
Front Fog Lamp Switch: The scan tool the front fog lamp switch. The scan tool displays ACTIVE or INACTIVE when the switch is depressed. The BCM uses this data in controlling the operation of the front fog lamps.
Flash to Pass Switch: The scan tool displays the position of the flash to pass switch. The scan tool displays On when the switch is pulled to activate the high beams momentarily while the switch is held.
Headlamp Switch: The scan tool displays the position of the headlamp switch. The scan tool displays Active when the headlamp switch is in the ON position. The BCM uses this data in controlling the operation of the headlamps.
High Beam Switch: The scan tool displays the position of the high beam switch. The scan tool displays On when the switch is used to activate the high beams.
Ignition 0: The scan tool displays the position of the ignition switch. The scan tool displays On when the ignition switch is in the RUN or CRANK position.
Ignition 1: The scan tool displays the position of the ignition switch. The scan tool displays On when the ignition switch is in the RUN or CRANK position.
Ignition Accessory: The scan tool displays the position of the ignition switch. The scan tool displays On when the ignition switch is in the ACCY position only.
Inadvertent Power Relay: The scan tool displays the state of the inadvertent power battery rundown protection feature of the BCM. The scan tool displays Off when all inadvertent power circuits are functioning normally.
Interior Lamp Defeat Switch: The scan tool displays the position of the courtesy/dome lamp override switch. The scan tool displays On when the switch is activated requesting the BCM to override the normal interior lamp activation inputs and deactivate the interior lighting.
Key in Ignition: The scan tool displays Yes when the key has been inserted into the ignition switch. The scan tool displays No after the key has been removed.
Park Brake Switch: The scan tool displays the position of the park brake pedal. The scan tool displays Set when the park brake is engaged closing the switch. The BCM uses this data in controlling the operation of the park brake indicator, the reminder chime feature and the DRL system.
Park Lamp Switch: The scan tool displays the position of the park lamp switch. The scan tool displays ON when the park lamp switch is in the ON position. The BCM uses this data in controlling the operation of the park lamps.
OUTPUTS
High Beams: The scan tool displays the commanded state of the high beam relay. The scan tool displays On when the BCM allows the high beam relay to go to ground activating the high beam headlamps.
Low Beams: The scan tool displays the commanded state of the low beam relay. The scan tool displays ON when the BCM allows the high beam relay to go to activate the low beam headlamps.
Park Lamp Relay: The scan tool displays the commanded state of the park lamp relay. The scan tool displays ON when the BCM allows the park lamp relay to activate the park lamps.
Dimming Level: The scan tool displays the commanded state of the interior dimmable lamps. The scan tool displays a percentage based on the position of the thumb wheel.
Daytime Running Lamps: The scan tool displays the commanded state of the daytime running lamps (DRL). The scan tool displays ON when the BCM allows the DRL relay to activate the DRL.
OUTPUT CONTROL
Dimming Level: The scan tool displays the duty cycle of the pulse width modulated (PWM) signal distributed by the BCM to the interior lighting circuits. The scan tool displays 0 percent when the interior lamps illumination is OFF. The scan tool displays 100 percent when the interior lamp illumination is at full intensity.
Daytime Running Lamps: The scan tool displays the commanded state of the daytime running lamps (DRL). The scan tool displays On when the BCM illuminates the DRL.
Park Lamp Relay: The scan tool displays the commanded state of the park lamp relay. The scan tool displays On when the BCM allows the park lamp relay to go to ground to activate the park lamps.
RENDER: 1.0x
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.