Battery positive voltage (B+) is applied at all times through the left underhood fuse block BODY 1 Fuse to the switch side of the park lamps relay in the rear compartment relay center 2 via CKT 1342 (RED). When the headlamp switch is in the PARK or HEAD position, or the front foglamps switch is enabled, the instrument cluster park lamps input is grounded via CKT 74 (LT BLU) and the headlamp switch. In response to this input, the instrument cluster sends a request via the Class 2 serial data line to the body control module (PZM) to activate the park lamps. The PZM applies battery positive voltage (B+) to the coil side of the park lamp relay via CKT 352 (WHT). The coil receives ground through the headlamp switch via CKT 308 (GRY/BLK). The coil of the park lamps relay is then energized, closing the switch contacts. Battery positive voltage (B+) is then applied through the park lamps relay via CKT 256 (PPL) to the LT PARK Fuse and the RT PARK Fuse to the left and right park lamps respectively.

When the twilight sentinel is activated and the ambient light sensor indicates darkness, the PZM applies battery positive voltage (B+) to the coil of the park lamp relay. The PZM also provides ground for the coil. The park lamps are then activated as previously described when activated from the headlamp switch.

With the ignition switch in the RUN position, battery positive voltage (B+) is applied from the TURN Fuse via CKT 141 (BRN), through the turn signal flasher to the normally closed switch in the turn/hazard switch via CKT 16 (PPL).

With the turn switch in the left turn position, battery positive voltage (B+) is applied through the turn switch and through two paths to the lamps. One path is to the left front turn lamps via CKT 14 (LT BLU) and the left turn indicator input of the instrument cluster. The second path is applied to the left tail/turn lamps via CKT 18 (YEL) (USA) or CKT 1334 (YEL/BLK) (EXPORT). The lamps go on immediately. They begin to flash when the current heats up the timing element in the flasher and opens the switch. The turn signal flasher switch closes when the timing element cools. The flasher repeatedly opens and closes the circuit causing the turn lamps to flash. A similar procedure is followed when the turn switch is in the Right Turn position. One path is to the right front turn lamps via CKT 15 (DK BLU) and the right turn indicator input of the instrument cluster. The second path is applied to the right tail/turn lamps via CKT 19 (DK GRN) (USA and Eldorado EXPORT) or CKT 1335 (YEL/BLK) (DeVille EXPORT).

Battery positive voltage (B+) is applied at all times from the HAZARD Fuse via CKT 740 (ORN) through the hazard flasher to the normally open switch in the turn/hazard switch via CKT 27 (BRN). With the hazard switch in HAZARD, battery positive voltage (B+) is applied through the assembly to all four paths used by both front and rear turn lamps. All turn lamps and both indicators flash on and off. When in the HAZARD position, the turn circuit is opened within the turn/hazard switch and the flasher controls the lamps even if a turn has been indicated.

Battery positive voltage (B+) is applied at all times through the STOP Fuse to the stoplamp/BTSI switch via CKT 1540 (ORN). When the brake pedal is pressed, the switch closes and battery positive voltage (B+) is applied through the stoplamp/BTSI switch to the normally closed turn/hazard switch via CKT 20 (LT BLU). Battery positive voltage (B+) is also applied to all tail/turn lamps and the high mounted stop lamp via CKT 20 (LT BLU) causing the stop lamps to light.

For export vehicles battery positive voltage (B+) is applied at all times through the STOP Fuse to the stoplamp/BTSI switch via CKT 1540 (ORN). When the brake pedal is pressed, the switch closes and battery positive voltage (B+) is applied through the stoplamp/BTSI switch directly to the tail/stop lamps and the high mounted stop lamp via CKT 20 (LT BLU) causing the stop lamps to light.

With the ignition switch in the RUN position, battery positive voltage (B+) is applied from the CNR LP Fuse via CKT 241 (BRN) to the turn/hazard switch. The cornering lamps are permanently grounded to G101. With the turn switch in either the left turn or right turn position, battery positive voltage (B+) is applied to the respective cornering lamp. The cornering lamp then lights.