Dakota Quad Cab 2WD V6-3.9L VIN X (2002)
Seat Belt Reminder Lamp: Description and Operation
A seatbelt indicator is standard equipment on all instrument clusters. The seatbelt indicator is located in the Information Center area of the instrument
cluster, to the right of center. The seatbelt indicator consists of a stencil-like cutout of the International Control and Display Symbol icon for "Seat Belt"
in the opaque layer of the instrument cluster overlay The dark outer layer of the overlay prevents the indicator from being clearly visible when it is not
illuminated. A red Light Emitting Diode (LED) behind the cutout in the opaque layer of the overlay causes the icon to appear in red through the
translucent outer layer of the overlay when the indicator is illuminated from behind by the LED, which is soldered onto the instrument cluster electronic
circuit board. The seatbelt indicator is serviced as a unit with the instrument cluster.
The seatbelt indicator gives an indication to the vehicle operator of the status of the driver side front seatbelt. This indicator is controlled by a transistor
on the instrument cluster circuit board based upon cluster programming and a hard wired input from the seatbelt switch in the driver side front seatbelt
retractor through the seat belt indicator driver circuit. The seatbelt indicator Light Emitting Diode (LED) is completely controlled by the instrument
cluster logic circuit, and that logic will only allow this indicator to operate when the instrument cluster receives a battery current input on the fused
ignition switch output (RUN/START) circuit. Therefore, the LED will always be OFF when the ignition switch is in any position except ON or Start.
The LED only illuminates when it is provided a path to ground by the instrument cluster transistor. The instrument cluster will turn on the seatbelt
indicator for the following reasons:
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Seatbelt Reminder Function - Each time the cluster receives a battery current input on the fused ignition switch output (RUN/START) circuit,
the indicator will be illuminated as a seatbelt reminder for about seven seconds, or until the ignition switch is turned to the OFF position,
whichever occurs first. This reminder function will occur regardless of the status of the seatbelt switch input to the cluster.
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Driver Side Front Seatbelt Not Buckled - Following the seatbelt reminder function, each time the cluster detects an open circuit on the seat belt
indicator driver circuit (seatbelt switch open = seat- belt unbuckled) with the ignition switch in the Start or ON positions, the indicator will be
illuminated. The seatbelt indicator remains illuminated until the seat belt indicator driver input to the cluster is closed to ground (seatbelt switch
closed = seatbelt buckled), or until the ignition switch is turned to the OFF position, whichever occurs first.
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Airbag Indicator Backup - If the instrument cluster detects a fault in the airbag indicator circuit it will send a message indicating the fault to the
Airbag Control Module (ACM), then flash the seatbelt indicator ON and OFF. The cluster will continue to flash the seatbelt indicator until the
airbag indicator circuit fault is resolved, or until the ignition switch is turned to the OFF position, whichever occurs first.
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Actuator Test - Each time the cluster is put through the actuator test, the indicator will be turned ON, then OFF again during the bulb check
portion of the test to confirm the functionality of the LED and the cluster control circuitry.
The seatbelt switch input to the instrument cluster circuitry can be diagnosed using conventional diagnostic tools and methods. For further diagnosis of
the seatbelt indicator or the instrument cluster circuitry that controls the LED, (Refer to INSTRUMENT CLUSTER - DIAGNOSIS AND TESTING).
