Use the Scan Tool Data Display Values and Definitions Information in order
to assist in diagnosing vehicle malfunctions. Compare the vehicles
actual scan tool data with the typical data display value table information.
Use the data information in order to aid in understanding the nature
of the problem when the vehicle does not match with the typical data
display values.
The scan tool data values were taken from a known good vehicle under the following
conditions:
• | The ignition switch is in the ON position. |
• | The engine is not running. |
• | The vehicle is in PARK. |
ALC Light Sensor: This BCM input is used to determine the amount
of ambient light present. It has a voltage range of 0.4 volts (light) to
4.4 volts (dark).
Battery 1: This BCM input is used to determine the available
system voltage of the vehicle's battery.
Dome Lamp Command: This BCM input shows the requested state
of the dome lamp. On is displayed when the dome lamp is requested.
Dome Lamp Feedback: This BCM input is used to determine the
state of the dome lamp. Low is displayed when the dome lamp is active.
Driver Door Switch: This BCM input is used to determine if
the driver door is open. The BCM uses this input to perform various functions such
as chimes and interior lamp control. Low is displayed when the driver door is open.
DRL Relay Command: This body control module output displays
the state of the daytime running lamps (DRL) relay. When the proper conditions
are present for the BCM to command on the DRL relay by providing ground to
the relay, ON is displayed.
DRL Relay Feedback: This body control module output displays
the state of the daytime running lamps (DRL) relay. Low is displayed when the DRL
relay is active.
Headlamp Fdbk.: This BCM output displays the state of the headlamps.
Low is displayed when the headlamps are active.
Inadvertent Power Cmd.: This BCM output displays the state
of the inadvertent power relay that is internal to the BCM. The BCM uses this output
to provide battery voltage to the courtesy lamps. If the BCM senses that
a lamp has been illuminated for approximately 20 minutes after exiting the
vehicle, the BCM will turn off the inadvertent power relay to protect the
battery from run-down. On is displayed when the inadvertent power circuit is active.
Inadvertent Power Fdbk.: This BCM output displays the state
of the inadvertent power relay. Low is displayed when the inadvertent power relay
is active.
I/P Dimmer Input: The BCM uses this input to determine the requested
intensity of the I/P lamps. A voltage range of 0.57 volts (full intensity
illumination) to 4 volts (lowest intensity illumination) is shown.
I/P Dimmer Output: The BCM uses this output to control the intensity
of the I/P lamps. A % Duty Cycle (DC) range of 100% (full intensity illumination)
to 19% (lowest intensity illumination) is shown.
Key In Ignition: The BCM uses this input to determine if the
ignition key is inserted into the ignition cylinder. Yes is displayed if a key is
present in the ignition cylinder.
Low Beam Input: This body control module input displays the
state of the low beam headlamps. When the BCM senses that the normal low beam headlamps
are illuminated, a voltage reading of approximately 4.8 volts is displayed.
When the low beam headlamps are not illuminated, battery voltage should be displayed.
Low Beam Input = DRL: This body control module input displays
the state of the daytime running lamps (DRL). Yes is displayed when the DRLs are
active.
Low Beam Input = High: This body control module input displays
the state of the low beam headlamps. When the BCM senses that the low beam headlamps
are illuminated, No is displayed.
Low Beam Input = Off: This body control module input displays
the state of the low beam headlamps. When the BCM senses that the normal low beam
headlamps are illuminated, No is displayed.
Low Beam Switch: This body control module input displays the
state of the low beam headlamps. When the BCM senses that the normal low beam headlamps
are illuminated, On is displayed.
Parklamp Cmd.: This body control module output displays the
commanded state of the parklamp relay. When the parklamp relay is requested, On
is displayed.
Parklamp Input: This body control module input displays the
state of the park lamps. When the BCM senses that the park lamps are illuminated,
ON is displayed.
Parklamp Switch: This body control module input displays the
state of the park lamp switch. When the BCM senses that the headlamp switch is
in the headlamp or park lamp position, On is displayed.
Pass Door Switches: This BCM input is used to determine if
a passenger door is open. The BCM uses this input to perform various functions
such as chimes and interior lamp control. Low is displayed when a passenger door
is open.