Cherokee 4WD L6-4.0L VIN S (1998)
Malfunction Lamp / Indicator: Description and Operation
SYSTEM OPERATION
The airbag indicator lamp gives an indication when the airbag system is faulty or inoperative. The lamp is turned on by the instrument cluster
circuitry for about seven seconds when the ignition switch is turned to the On position as a bulb test. After the bulb test, the lamp is controlled by
the instrument cluster circuitry based upon a message received from the Airbag Control Module (ACM) on the Chrysler Collision Detection
(CCD) data bus.
The ACM continually monitors the airbag system circuits and sensors to decide whether the system is in good operating condition. The ACM then
sends the proper message to the instrument cluster on the CCD data bus to turn the lamp on or off. If the ACM sends a lamp-on message after the
bulb test, it indicates that the ACM has detected a system malfunction and/or that the airbag system has become inoperative.
Each time the instrument cluster circuitry receives a lamp-on message from the ACM, it will light the lamp for twelve seconds or the duration of
the airbag system malfunction, whichever is longer. If the instrument cluster receives no lamp messages from the ACM for more than five seconds,
it will light the lamp for twelve seconds or until another lamp-off message from the ACM, whichever is longer.
Refer to Air Bag Systems for more information on the airbag.
