Saturday, 30 June 2012

HP 6735B BLINK CAP LOCK 5 TIMES, NO OTHER ACTIVITY- SOLVED

SORRY I WILL NO BE ABLE TO ADD PICTURES HERE BECAUSE AM VERY BUSY THIS PERIOD BUT IT WILL BE AVAILABLE ANYTIME AM DISPOSED.
I READ A LOT OF SOLUTION ON GOOGLE ON USING OVEN TO SOLVE IT BUT I HAVE TRYED IT SEVERAL AND DISCOVERED THAT YOU HAVE ONLY 10% CHANCE OF SUCCESS.
ACTUALLY THIS PROBLEM IS RELATED TO 1.MISSING COMPONENT DUE TO HEAT WHICH CAN BE FOUND BY CAREFUL INSPECTION OF THE MOTHERBOARD. 2. FROM THE AMD NORTH AND SOUTH BRIDGE. 3. FROM SHORTED MOSFET BUT THIS ONE IS NOT COMMON.
NO 2 IS MOST COMMON AND THE BEST WAY TO SOLVE IT WITHOUT REPLACING THE CHIP IS TO USE BGA REWORK STATION. SET THE PRE-HEATER  AT 270C AND PLACE THE MOTHERBOARD FOR 2 MINUTES, THEN SWITCH ON INFRARED FOR 90 SECONDS AND ALLOW IT TO COOL.THAT'S ALL.REMEMBER TO CLEAN THE FAN CLOGS

Tuesday, 26 June 2012

hp dv7 no light no power and doesnt charge battery

the customer brought it to my desk that he just finishing charging the laptop an d after that switch it on it refuse to on. i dessamble the laptop and check the mosfet in this one is 6676, the mosfet immediately after the power connector and discover it was burnt. changed it with ao4377 from another board and it charge battery but cannot power. then i check other components around it, all okay except voltage regulator that is shorted. now system work fine

DV SERIES NO POST AND BLINKING LIGHT

 THIS TYPE OF FAULT IS ALWAYS FROM A FAULY COMPONENT OR MISSING PARTS NEAR THE SOUTH OR NORTH BRIGE. SO CAREFULLY LOOK FOR FALLING PARTS DUE TO EXCESS HEAT. So look at  the cap that was to be seated on the South Bridge was sitting on the edge of it. Totally out of place.   I always look closely at the motherboard before attempting repairs. Parts get old, solder gets weak.