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. |
DRL Relay: This body control module (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 BCM input displays the state of the
DRL relay. When the BCM senses that the DRL relay is on, ACTIVE is displayed.
Park Lamp Input: This BCM input displays the state of the park
lamps. When the BCM senses that the park lamps are illuminated, ON is displayed.
Low Beam Feedback: This BCM input displays the state of the
low beam headlamps. When the BCM senses that the normal low beam headlamps are illuminated,
the operating voltage of the low beam headlamps is displayed. When the BCM
senses that the DRLs are active, the reduced operating voltage of the DRLs
is displayed.
High Beam Feedback: This BCM input displays the state of the
high beam headlamps. When the BCM senses that the normal high beam headlamps are
illuminated, the operating voltage of the high beam headlamps is displayed.
When the BCM senses that the DRLs are active, the reduced operating voltage
of the DRLs is displayed.
Interior Dim Pot: The BCM uses this input to determine
the requested level of the instrument panel dimming lamps. When full intensity is
requested, the scan tool will display less than 1 volt. When full dim is requested,
the scan tool will display approximately battery voltage. The voltage will vary
within this range depending on the position of the lamp dimmer switch.
Interior Lamp Output: This BCM output displays the state of
the interior courtesy lamps. When the BCM is commanding on the interior courtesy
lamps by providing ground to the lamps, ON is displayed.
Driver Door Ajar 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. ON is displayed when the driver door
is open.
Passenger Door Ajar Switch: 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. ON is displayed when a passenger door
is open.
Inadvertent Power Output: 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.
Inadvertent Power Feedback: This BCM input displays the state
of the inadvertent power relay. When the BCM senses that the relay is on, ACTIVE
is displayed.
Cargo Lamp On: This input to the BCM is used to determine if
the rear compartment lid is open or closed. If the rear compartment lamp is on, the
scan tool displays ON. The BCM uses this input for theft deterrent purposes.