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. |
Ambient Light Sensor: This body control module (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 vehicles 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 BCM 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 DRL relay. Low is displayed when the DRL relay is active.
Fog Lamp Relay Cmd.: This BCM output displays the state of the
fog lamp relay control circuit. The BCM uses this output to provide a ground to the
fog lamp relay, illuminating the fog lamps.
Fog Lamp Relay Fdbk.: This BCM output displays the state of
the fog lamp relay. Low is displayed when the fog lamp relay is active.
Fog Lamp Switch: This BCM input is used to determine if the
fog lamps are requested. On is displayed when the fog lamp switch is pressed.
High Beam Switch: This BCM input displays the state of the
high beam headlamps. When the BCM senses that the normal high beam headlamps are
illuminated, On is displayed.
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. High is displayed when the inadvertent power relay
is active.
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.
Liftgate Ajar Switch: This BCM input is used to determine if
the liftgate is open. The BCM uses this input to perform various functions such
as chimes and interior lamp control. Low is displayed when the liftgate is open.
Low Beam Input: This BCM 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 0.4 volts is displayed. When the low beam
headlamps are not illuminated, battery voltage should be displayed.
Low Beam Input = DRL: This BCM input displays the state of
the DRL. Yes is displayed when the DRLs are active.
Low Beam Input = High: This BCM 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 BCM input displays the state of
the low beam headlamps. When the BCM senses that the normal low beam headlamps are
illuminated, Yes is displayed.
Park Brake Switch: This BCM input is used to determine if the
park brake is set. The BCM uses this input to determine if daytime running lamps should
be requested during daylight driving.
Parklamp Switch: This BCM 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.