Introduction To Display And Keyboard Backlight Troubleshooting - Nokia 6720 Service Manual

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BB Troubleshooting and Manual Tuning Guide

Introduction to display and keyboard backlight troubleshooting

Display and keyboard lights are handled by Gazoo (EM ASIC) internal LED drive. It has one output pin, but two
independent LED branches (display and keyboard) which can have different number of LEDs (2 to 4). Keyboard
and display branch of LED network can be enabled and disabled independently from Gazoo LedCR register or
using Phoenix display test program. Display LEDs are located inside the display and keyboard LEDs are on the
PWB.
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