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Circuit/System Description

WARNING: This page is about a different car, the 2011 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.

All Countries Except Japan, Korea, Taiwan 

Voltage is applied at all times to the PRK LAMP relay from battery voltage. When the headlamp switch is placed in the PARK position, ground is applied through the park lamp switch ON signal circuit to the body control module (BCM) . The BCM then applies a ground to the park lamp relay control circuit. This energizes the relay and applies voltage through both PRK LAMP fuses and the park lamp supply voltage circuits illuminating the park, tail, and license lamps.

Japan, Korea, Taiwan Only 

Voltage is applied at all times to the PRK LAMP relay and the RT PRK LAMP relay from battery voltage. When the headlamp switch is placed in the PARK position, ground is applied through the park lamp switch signal circuit to the BCM. The BCM then applies a ground to both the park lamp relay control circuits. This energizes the relays and applies voltage through both PRK LAMP fuses and the park lamp supply voltage circuits illuminating the park, tail, and license lamps.