Hi there are two Z510 notebooks, as per customers descriptions one is water damaged and other one has stopped suddenly. the first one was taken to another repair shop and they have reflowed KBC and reflashed both BIOS chips without any success.

Both boards don't have +3VALW and +5VALW, the ic is RT8243AZQW and supply is OK, there are two jumpers PJ401 and PJ402 which distribute +3VALWP and +5VALWP to +3VALW and +5VALW.
Voltage at PL401 (3.3v) is 0.3 volt and PL403 (5v) is zero volts. when i remove jumper PJ401 (+3VALWP ---> +3VALW), 3.3volt and 5volt start to appear at corresponding coils.

Any ideas? Also KBC is IT8586, if replaced, does it need to be programmed?

Thanks in advance.

Yes. Take a here.


Remove PJ401, connect adjustable power supply (APS) on side +3VALW (pad 1 on schematic). Set up 3V and 1A on APS and power-on APS. Feel by fingers a motherboard all surface on abnormal heating. If heat small or not feel, step up current on 0.5A and again. The broken component will abnormal heating. Probably APS will work in mode "Current limit". This normal if on mother board have a broken component .

Thanks for the reply, will try it, about it8586 the only programmer that I have found is svod, any other alternatives you know? how about svod itself, has anybody have experience?

Thanks.

I chose a long time and chose programmer by S.Vertyanov. I really like this programmer. You can buy it here. You can read and post your questions here.

I removed PJ401 and applied 3.3V using current limited power supply, and the maximum current reached 800mA, couldn't find any abnormal heating. I suspect that it might not be a short problem but somehow related to KBC, because in the schematics, OCP for PU904 (RT8243AZQWE2) is much higher that 5 Amps and somehow Pin 13 (Enable) is related with some signals coming from EC. What's your opinion.

Thanks.

replace PU904. Check the associated components, especially the feedback resistors.

I have checked surrounding resistors, replaced RT8243 (PU904) again the problem persists, also checked feedback voltages, 2v at pins 1,5 available. The point is with PJ401 removed, there is enable signal to PU904, but when PJ401 soldered, Enable is not available.

thanks

The problem has been solved, PCH had been short, replaced it and voltages came back and laptop turned on.