U8185
Maintenance Manual
9 Principles and Failure Analysis
Issue 1.0 (2012-03-23)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
49
Figure 9-13
Troubleshooting for LCD display failure
LCD display failure
Y
N
N
N
Y
Y
Y
Y
N
N
Y
Y
N
N
Y
Y
N
N
Is the BTB socket
properly connected?
Y
N
Connect the BTB
socket
Is the power supply
to the LCD normal?
Troubleshoot power
supply problem
Re-install the
software. Problem
solved?
End
Is the BTB socket
properly soldered?
Re-solder it
Replace the LCD.
Problem solved?
Follow the soldering
specification.
End
End
Table 9-3
Circuit diagram signal summary
Signal
Description
Reference Measurement or
Wave Form
LCDC_RESET_N
Reset signal; valid when at low level
None.
LCDC_BLUE
Blue data bus
None.
LCDC_GREEN
Green data bus
None.
LCDC_RED
Red data bus
None.
LCDC_SPI_CS
Chip select signal; valid when at low level
None.
LCDC_SPI_SCLK
Serial clock signal
None.
LCDC_SPI_SDO
Serial data output signal
None.
LCDC_SPI_SDI
Serial data input signal
None.