Keypad Backlight Troubleshooting - Nokia 6235 Baseband Description And Troubleshooting

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set for all the branches by Rset which in this case is 12k Ohms and equates to 10mA
through each LED.

Keypad Backlight Troubleshooting

When troubleshooting keypad backlight, make these common checks (see
Figure 30):
• Performed visual inspection of all the components including LED's
• Check Vbat to make sure Driver has power
• Check Klight to make sure driver is enable by UEMEK. If not correct, check
UEMEK
• If light are too dim or too bright, check Rset. Rset controls the current going
through the LED's.
• Check Vout to make sure LED's are getting power, if still not working change LED.
Make sure LED orientation is correct.
Issue 1 04/2005
Figure 25: Keypad Backlight Diagram
©2005 Nokia Corporation
6235/6235i/6236i (RM-60)
Baseband Description and Troubleshooting
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Figure 29 and
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