RAM 1500 Truck 4WD V8-5.9L VIN Z (2002)
Air Bag Deactivation Switch: Description and Operation
Fig. 38 Passenger Airbag ON/OFF Switch
PASSENGER AIRBAG ON/OFF SWITCH
The passenger airbag ON/OFF switch is standard equipment on all standard cab versions of this model when they are equipped with the dual front
airbag system. This switch is a two-position, resistor multiplexed switch with a single integral red Light-Emitting Diode (LED), and a non-coded
key cylinder-type actuator. The switch is located in the lower right corner of instrument panel center bezel, near the center of instrument panel to
make the OFF indicator visible to all front seat occupants. When the switch is in its installed position, the only components visible through the
dedicated opening of the cluster bezel are the switch face plate and nomenclature and the key cylinder actuator. The "OFF' position of the switch is
illuminated when this switch position is selected, while the "ON" position of the switch is designated by text imprinted upon the face plate of the
switch, but is not illuminated. The remainder of the switch is concealed behind the switch face plate and the instrument panel center bezel.
The passenger airbag ON/OFF switch housing is constructed of molded plastic and has three integral mounting tabs. These mounting tabs are used
to secure the switch to the back of the molded plastic switch face plate with three small screws. The molded plastic face plate also has three
integral mounting tabs that are used to secure the switch and face plate unit to the instrument panel center bezel with three additional screws. A
molded plastic connector receptacle on the back of the switch housing connects the switch to the vehicle electrical system through a dedicated take
out and connector of the instrument panel wire harness. The molded plastic harness connector insulator is keyed and latched to ensure proper and
secure switch electrical connections. The passenger airbag ON/OFF switch cannot be adjusted or repaired and, if faulty or damaged, the switch
must be replaced.
The passenger airbag ON/OFF switch allows the customer to turn the passenger airbag function ON or OFF to accommodate certain uses of the
right front seating position where airbag protection may not be desired. See the owner's manual in the vehicle glove box for specific
recommendations on when to enable or disable the passenger airbag. The OFF indicator of the switch will be illuminated whenever the switch is
turned to the OFF position and for 2 seconds at ignition ON for an indicator bulb test. The switch assembly is mounted in the center of instrument
panel to make the OFF indicator visible to all front seat occupants. The ignition key is the only key or object that should ever be inserted into the
switch. The ON/OFF switch requires only a partial key insertion to fully depress a spring-loaded locking plunger. The spring-loaded locking
plunger prevents the user from leaving the key in the switch. The key will be automatically ejected when force is not applied. To actuate the
passenger airbag ON/OFF switch, insert the ignition key into the switch key actuator far enough to fully depress the plunger, then rotate the
actuator to the desired switch position. When the switch key actuator is rotated to its clockwise stop (the key actuator slot will be aligned with the
OFF indicator), the OFF indicator is illuminated and the passenger airbag is disabled. When the switch is rotated to its counterclockwise stop (the
key actuator slot will be in a vertical position), the OFF indicator will be extinguished and the passenger airbag is enabled.
The passenger airbag ON/OFF switch connects one of two internal resistors in series between the passenger airbag mux switch sense and
passenger airbag mux switch return circuits of the Airbag Control Module (ACM). The ACM continually monitors the resistance in these circuits
to determine the switch position that has been selected and to provide circuit diagnostics. The ON/OFF switch ON position resistance is 175 - 190
ohms and the OFF position resistance is 820 - 870 ohms. If the ON/OFF switch circuits are open, shorted to ground or battery the ACM will set
active and stored DTC. Upon receiving a switch diagnostic trouble code the airbag warning indicator, in the instrument cluster, will be turned ON
by the ACM. Whenever the airbag warning indicator is illuminated, the ACM should be the first module interrogated.
When the switch is in the OFF position, the ACM provides a ground input to the switch through the passenger airbag indicator driver circuit,
which energizes the Light-Emitting Diode (LED) that illuminates the OFF indicator of the switch. The ACM will also illuminate the OFF indicator
of the switch for about 2 seconds each time the ignition switch is turned to the ON position as a bulb test. The ACM will also store a Diagnostic
Trouble Code (DTC) for any fault it detects in the passenger airbag ON/OFF switch or indicator circuits, and will illuminate the airbag indicator in
the instrument cluster if a fault is detected. For proper diagnosis of the passenger airbag ON/OFF switch or the ACM, a DRB III scan tool is
