Mga Pahina

Wednesday, January 3, 2018

Dell Laptop QAL80 LA-7781P No Display Problem

Case Study : Dell Laptop
Part No : QAL80 LA-7781P
Problem : No Display
Solution : Found that only stuck in 0.150 amp on PSU. Step down Ic (3.3 v /5 v ) heating.
Checked For short Circuit Not Found. Then checked the RTC 3.3 v it was 0 volt  Replaced RTC Cell Then Also no voltage RTC. At Last Found  Pf Leaky
Laptop Working Fine

Tuesday, January 2, 2018

Acer Aspire E5-573 No Power On and Not Charging

Model:Acer Aspire E5-573

MB ID:ZRT

Case Study Problem : plugged in adaptor no power on and not charging

Solution : First I check VIN present, no auxuliary voltages at battery connectors.
I check with PSU 19V, it takes 0.28amp then decrease voltage from 19v to 17v.
now the laptop power on and working fine. So the problem is located at the power IC pin(6) 2.59v (acdet).
I check voltage divider working ok as in schematic
Now I replace 8k resistance in place of 10k now am getting voltage is 2.13v (63.4k-10k actual)
ok i give 19v from PSU ...LAPTOP is working fine.