Sam4s SAP-630 Series - Back-light, LCD, Data Memory, RTC, Battery Problem

6 Troubleshooting
SAM4S SAP-630 SERIES 6-3
6-3 Back-light, LCD, Data Memory, RTC, Battery Problem
6-3-1 Back-light of TFT-LCD problem
 Check the back-light voltage (VLED+ 19.2V) on LCD B’D.
 Check harness
→ Harness between MAIN B’D and LCD B’D (30-pin).
→ Harness between LCD B’D and TFT-LCD (IPEX cable 30-pin).
 Check the signal (Back-light adjust signal)
→ Check this signal whether it short / open.
6-3-2 TFT-LCD panel problem (No display)
 Check the LCD LVDS signals at LVDS Connector on Main B’D.
→ Measure these signals and check whether it short/open or not
 Check harness.
→ Harness between Main B’D and LCD B’D. (20-pin).
 Check the voltage VLCD3.3V. This voltage is used for TFT-LCD panel logic.(MAIN B’D output)
 Check the LVDS Cable between LCD B’D and TFT-LCD panel (IPEX CABLE 30-pin)
6-3-3 RTC problem
 Check backup circuit on MAIN B’D
→ Check the RTC clock, this frequency is 32.768KHz
→ Check battery voltage whether above 2.5V or not.