Sam4s NR-500R Service Manual page 69

8-3 LCD Display Problem
LCD Problem
Power VDD3.3V,
Ok?
Disconnect
Back Light
LCD Display
LCD PBA
Assy Ok?
SAM4S NR-500 SERIES
N
Y
N
Ok?
Y
N
OK?
Y
N
OK?
Y
N
Y
End
1. Refer to the Power Problem.
2. Check the Harness.
1. Check the Harness.
2. Check the LCD Disconnection Signal Pattern.
1. Check the LCDBL_ONOFF signal(CPU P8.6).
: It controls LCD back light ON/OFF.
2. Check the KSA1182(Q15,Q21),MMBT222A(Q22) and
related Circuit.
3. Check the LCD Backlit harness Status.
1. Check the D/I Signal (CPU P9.0)
2. Check the SCLK Signal (CPU P9.1)
3. Check the SDAT Signal (CPU P4.7)
4. Check the Harness.
1. Check the LCD.
2. Check and Replace the LCD MODULE PBA.
3. Check the LCD Harness.
8 Troubleshooting
8-3