When the headlamp switch is turned to the park position, a ground is applied through the headlamp switch to the parklamp switch output circuit to the BCM. The BCM then applies a ground to the park lamp relay coil control circuit. This energizes the PARK LP relay and closes the switched sides of the relay allowing B+ to be applied to the REAR PARK LP fuse. B+ is then applied thorough the rear park lamp fused circuit to the I/P dimming switch in the headlamp switch. The I/P dimming switch varies the voltage level to the interior lamps, dimming or brightening them accordingly through the I/P dimming switch circuit. The grounds for the interior lamps is applied at all times.

The varied B+ is applied to the STEERING COLUMN fuse from the I/P dimming switch circuit. The varied voltage is then applied through the steering column fuse circuit, through the inflatable restraint steering wheel module coil then to all of the steering wheel controls turning them on. The ground for the steering wheel controls is applied at all times.