Service manual

8 Trouble Shooting
SAM4S ER-650 SERIES 8-3
8-3 LCD Display Problem
End
LCD Problem
Reset Signal
Ok?
Y
N
1. Refer to the Reset Part of System Problem
2. Check the Harness
Data Signal
Ok?
Control Line
Ok?
Y
1. Check the CPU F_LCD_CS1 (P1.0)
2. Check the CPU F_LCD_CS2 (P1.1)
3. Check the CPU LCD_RW (P7.4)
4. Check the LCD_DI (P8.2)
1. Check the Harness
2. Check the 74HC245 (U22)
3. Check the HC138 (U7) & LCD_CS Signal
4. Check the CPU /RD Signal
N
N
Back Light
Ok?
Y
Y
1. Check the CPU
INTP1 (P8.3)
2. Check the TR A473, 2222 (14,16)
3. Check the LF33CV (U27)
N
Contrast
Ok?
Y
1. Check the VR1(10K)
2. Check the LCD Output VO
3. Check the Harness
4. Check & Replace the LCD Module
N