Body Control Systems: Description and Operation

MODULE CONTROLLED FUNCTIONS

The vehicle security module is a multifunction module that controls several vehicle subsystems. The vehicle security module continually monitors and provides diagnostic information for the following:
- power locks
- remote keyless entry (RKE)/keyless entry (keypad)
- autolamps

Upfitter System

The upfitter system consists of:
- Four upfitter relays
- Upfitter relay box
- Upfitter switch assembly
- Four blunt cut relay controlled voltage circuits

The 4 upfitter system switches are low current on/off latch switches that control 2-10A and 2-30A, fused, voltage at all times, relays. The upfitter switches are not designed to carry any significant loads. They are designed to allow the driver to manually close the relay coil circuit. When the relay coil circuit is completed the relay contacts close and provide voltage to added options. The upfitter relays are located above the glove box. The relay and relay contacts are designed to carry the actual load that is being added to the vehicle. The output circuits of the upfitter relays go to the interior of the vehicle and are blunt cut. The blunt cut ends are located behind the central junction box (CJB) and are accessed through the opening in the instrument panel when the instrument panel steering column cover is removed. The upfitter switches are located in the instrument panel center finish panel under the climate control assembly. The upfitter switches have individually lighted indicators that illuminate when the switch is in the on position. The indicator lights for the individual upfitter switches are not controlled by the headlamp switch. The upfitter switch backlighting is adjustable and is controlled by the headlamp switch.