Dell E173FP Service Manual - Page 29

8.2 Trouble Shooting 8.2.1 Main Board 1) No display Measured CN104 pin 5 = 5 V? Measured U101 pin44=5V? Measured U105 pin 2= 3.3V? DELL E173FP Service Manual No DC Level Check Power board, is there DC level output?. Check U105 pin3=5V, P105 pin2=3.3V? Is there any shortage or cold solder or PCB trace is disconnected? Check Correspondent component Yes, all DC level exist Disconnected the Signal cable (Loose the Signal cable), Is the screen show Block WRGB color bars? Yes. There have OSD show Connected the Signal cable again, Check LED status. LED Green No, nothing is show Led Orange Connected the Signal cable again, Check LED status. Check Power switch is in Power-on status, and check if Power switch had been stuck? Replace U102 Scalar IC Led orange Led Green Check the Wire-Harness from CN101 OK, Keyboard no stuck Measured RGB (R112, R114) H, V Input at U102 pin 95, 96, was there have signal? Check Correspondent component short/open Protection Diode and NG Signal cable bad? OK, Wire tight enough Check Panel-Power Circuit Block OK, Panel Power Check U200 Data-output Block OK, U102 data OK Replace Inverter board and Check Inverter control relative OK, input Normal Measured Crystal X101 OK, clock normal Replace U102 (GMZan3SL) Re-do White balance OK Note: 1. If Replace "MAIN-BOARD", Please re-do "DDC-content" programmed & "WHITE-Balance". 2. If Replace "Inverter Board" only, Please re-do "WHITE-Balance" 29