MODEL : HP OMNI 120-1232IL___DA0WJ5MB6F0_REV: PROBLEM : RANDOMLY PROBLEM. SOMETIMES POWER ON AND DISPLY OK AND WORKING FINE FOR HOLEDAY. SOMETIMES POWER ON & THEN OFF. WITHOUT RAM ITS POWER ON FINE WITH RED LIGHT INDICATOR. WITH RAM SAME PROBLEM.

MODEL : HP OMNI 120-1232IL___DA0WJ5MB6F0_REV: PROBLEM : RANDOMLY PROBLEM. SOMETIMES POWER ON AND DISPLY OK AND WORKING FINE FOR HOLEDAY. SOMETIMES POWER ON & THEN OFF. WITHOUT RAM ITS POWER ON FINE WITH RED LIGHT INDICATOR. WITH RAM SAME PROBLEM. SCHEMATIC : NOT AVAILABLE BIOS : NOT AVAILABLE ON HP SITE SOLUTION : 1ST DO BIOS BOTH MAIN BIOS AND EC BIOS. STILL PROBLEM NOT SOLVE. THEN CHANGE NEW EC BIOS IC AND REPROGRAM IT. STILL PROBLEM NOT SOLVE. FIRST TIME WITHOUT SCHEMATIC IT'S VERY DIFFICULT TO TRACE THE PROBLEM. THEN TROUBLESHOOT RAM IC EF=EF (RT8207L) FROM ITS DATASHEET. ALL REQUIREMNTS ARE OK. THEN CHECK DDR-3 RAM SLOT REQUIREMENT. ALL REQUIREMENTS ARE OK. THEN GET IO IT8518E DATASHEET AND CHECK IO REQUIREMENT IT8518E USING DATASHEET. ALMOST ALL OK. EXCEPT THERMAL PROTECTION. NO ANY CLUE ABOUT THERMAL PROTECTION ON IO PINS. NOWWW... LITTLE CONFUSED AND SUDDENLY REMEMBER (THERMAL PROTECTION CONCEPT) SO I DIRECT CHECK CPU CONTROLLER IC (NCP6131). GET DATASHEET AND START STUDY ALL PINS FROM DATASHEET. I SHOW ONE PIN NAMED VRHOT# AND GOT CLUE. STUDY FULL DATASHEET WITH DETAILS SLOWLY SLOWLY AND GOT CLUE THAT VRHOT# CONNECT WITH ONE 0OHM REGISTER THEN 100K NTC REGISTER AND NTC OTHER SIDE GROUND. I TRACE THIS PIN IN MOTHERBOARD AND FINALLY FOUND FAULTY NTC 100K. REMOVE 100K NTC AND REPLACE WITH NEWONE. NOW PRESS THE POWER BUTTON. BOOM BOOM BOARD POWER ON PERFECTLY AND DISPLAY COME WITH TESTING HALLDAY. ITS WORKING FINE WITHOUT ANY PROBLEM Copyright Case Study For Learning