histar's Blogger: 九月 2015

2015年9月29日星期二

ASUS K43LY X84H laptop does not work, standby current 0.03A share

An asus x84h laptop, motherboard number K43LY, standby current 0.03A, do not output 3V and 5V, the notebook does not work.

Check power chip RT8206B, Linear 5V is normal to output. Check the 14-pin and 27-pin, have not voltage on them, the two signals are controlled to open by EC, so check the standby power supply for EC, 3.3V, it is normal. In theory the EC should send 3.3V switch signal, but it does not send the signal, so welding to open the controlling pin of EC, then test and there is 3.3V, so prove the EC chip works, it is no problem. Then replace a new power ic RT8206B, but it is same fault, yet. .... read more

W83194BR-39B SSOP48 IC

http://www.htic-tool.com/w83194br39b-ssop48-ic-p-1615.html

W83116WG-511 TSSOP64 IC

http://www.htic-tool.com/w83116wg511-tssop64-ic-p-1614.html

2015年9月26日星期六

HP431 don't trigger, common failing share

A HP431 laptop, the motherboard is same with CQ43, don’t trigger, don’t work. Insert the power adapter and connect the power supply, 0.022A standby current, Press the power button, the power led lights, But the current is very small 0.022-0.024A, almost have not big change. So think the Embed Controller chip works, but the chipset ( BD82HM65 ) does not trigger, because the embed controller control the power led and trigger led, and the current has a very small change after trigger.

Re-write the embed controller bios, the same fault yet. Find the schematic diagram (same with CQ43), check EC_PWRBTN# (from EC to HM65) first. .... read more

W83L351YG 351YG QFN-20 IC

http://www.htic-tool.com/w83l351yg-351yg-qfn20-ic-p-1613.html

WGI217LM QFN IC

http://www.htic-tool.com/wgi217lm-qfn-ic-p-1612.html

2015年9月24日星期四

Lenovo E43L Doesn’t Work Share

A lenovo E43L notebook, connect the power supply, standby current is 0.01A. Push the power button, the current up to 0.04A. But the lights are not bright. The laptop does not trigger properly.

Checked 5VPCU 3VPCU, they are normal. Checked the pin of power switch, it is 3.3V normal.

Push the button, checked conversion voltage 3V_S5 5V_S5, they are normal. But have not 3VSUS and 5VSUS voltage. Checked the switching control signal SUSON, have not this signal.

Test ACIN NBSWON# DNBSWON# S5_ON RSMRST#, they are normal. But checked SUSB#,SUSC# signal, have not voltage. Checked Embed Controller, 76 24 Pin, found 3Pin from RCT power supply. Connect the power supply, test RCT, only 1V. .... read more

WG82578DM QFN-48 IC

http://www.htic-tool.com/wg82578dm-qfn48-ic-p-1611.html

WG82577LM QFN IC

http://www.htic-tool.com/wg82577lm-qfn-ic-p-1610.html

2015年9月21日星期一

Green Screen Display Fault of Lenovo N440A Laptop Share

A Lenovo N440A laptop, can enter windows system, but display green screen. According to the experience of repairing, should be RGB circuit problem.

The display is normal when connecting an external monitor, so exclude the graphics card reason. Remove the screen cable to test, the cable is ok. Then doubt it is interface problem of motherboard. Check the resistance value between interface and GND. All are ok.

After checking, found the Pin4 and Pin5 are short circuit in U4, and capacitors C6,C8 are short circuit, too. So removed U4 and C6,C8, still there are short circuit. So removed KE5M6U2654 chip. the short circuit phenomenon disappear.... read more

WG82567LM QFN-48 IC

http://www.htic-tool.com/wg82567lm-qfn48-ic-p-1609.html

NPCE985PA0DX NPCE985PAODX QFP IC

http://www.htic-tool.com/npce985pa0dx-npce985paodx-qfp-ic-p-1608.html

2015年9月19日星期六

A strange reason : DELL M5110 notebook dark screen failure

A dell m5110 notebook display very dark. There are not seven times alarm sound when starting up. The current is normal. According to the repairing experience, usual it is the graphics card problem. Displaying is normal when connect an external monitor. So, .... read more