Circuit Description
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The SEO 1 15 A fuse in the engine wiring harness junction block supplies battery positive voltage to both the ground illumination relay switch contacts and the ground illumination relay coil circuit. When the driver or passenger door is opened the Body Control Module (BCM) energizes the ground illumination relay. Current flow is from the ground illumination relay to both outside rear view mirror ground illumination lamps. The ground illumination lamps are grounded through the courtesy lamps relay at G200 and G203.