Samsung Samsung repair tips free download

File name Samsung_repair_tips.txt

================================================================================ MODEL: Most Samsung plasmas -------------------------------------------------------------------------------- ISSUE: Cannot identify whether failure exists in main board, control board, sustains or PSU. -------------------------------------------------------------------------------- DIAGNOSIS: Locate test header on control - should be 4x2 or 6x2. Jumper appropriate pins (refer to service manual or PCB) If you get test patterns: - sustains, PSU, control okay - main bad (control POSSIBLY bad - if input receiver bad) If not: - sustains, PSU, control or main are bad Then identify failure in PSU - test output voltages - if bad, fault lies in PSU, shorted sustain or main not turning the PSU on Then identify sustain board failures: - unplug X-main, check if powers up and Y-main functions (dim picture) - unplug Y-main, check if powers up (no picture) Then identify control board failures: - test SMD fuses - scope LVDS waveforms going to control (if possible) Might be main board failure. To confirm, test main board: - blindly select audio source using INPUT button ================================================================================ ================================================================================ MODEL: PS42C7HD -------------------------------------------------------------------------------- FAULT: Clicking relay, no picture or sound -------------------------------------------------------------------------------- DIAGNOSIS: Identify shorted sustain board (X-main or Y-main) Unplug either board in succession and see if set stops clicking -------------------------------------------------------------------------------- FIX: Repair or replace the X or Y-main board ================================================================================ ================================================================================ MODEL: PS42C7HD -------------------------------------------------------------------------------- FAULT: No picture or picture with significant maldischarge -------------------------------------------------------------------------------- DIAGNOSIS: Requires oscilloscope Check Y-main waveform (was only about 20Vp-p, should be >400Vp-p) -------------------------------------------------------------------------------- FIX: Replace 100uF 50V cap near yellow trafo on Y-main board ================================================================================ =======================================================================