1508(RM-388)
Baseband Description and Troubleshooting
Nokia Customer
Care
Issue 1
Copyright © 2008 Nokia, All rights reserved
Display and Keypad
The mobile terminal uses light-emitting diodes (LEDs) for liquid crystal display (LCD)
and keypad illumination. There are two white LEDs for the LCD and two LEDs for the
keypad. KEYPAD_LED is the signal used to drive keypad LEDs. LCD_BL_EN is the
signal used to drive LCD LEDs. The mobile terminal uses a color LCD. The interface
uses a parallel bus to transfer the Command/ Data between CBP and LCD.
Troubleshooting
First, carry out a thorough visual check of the module. Make sure in particular that:
• There is no mechanical damage.
• Soldered joints are OK.
• ASIC orientations are OK.
The following hints should help find the cause of the problem when the circuitry
seems to be faulty. Troubleshooting instructions are divided into the following
sections:
• ‘Power Does Not Stay ON’
• “Charger Faults’
• ‘Audio Faults’
• ‘Display Faults’
• ‘Keypad Faults’
• ‘No Vibration’
• ‘Series/USB Interface Disabled’
• ‘UIM Card Unreadable’
Note:
• CBP5.6 is underfilled and can not be replaced.
• The Shielding Case Assy can not be reused after removal.
• After using the heatgun, the domesheet needs to be replaced.
To Next Page
Loading...
