LENOVO 320 turns on lights present cpu not spinning

[String2016]

I need help on this LENOVO IDEAPAD 320 DG425/DG525/DG725 NM-B321 Rev:1.0.The problem is turns on lights on the power button is present cpu is not spinning and no display, already tried reflashed with good bios and ec here in this forum but still same issue. i have attached the phone on the measurement of shorted coil and cap resistance coil is PL2202 and PL1401 and the cap is PC2251 I Dont have a schematic for this . anyone could help me solve this problem please

[mcplslg123]

Re: LENOVO 320 turns on lights present cpu not spinning

Both the coil resistance is fine. Coils on CPU/GPU are supposed to show low resistance.

[String2016]

Re: LENOVO 320 turns on lights present cpu not spinning

cpu here is cold but turns on and the fan is not spinnng

[String2016]

Re: LENOVO 320 turns on lights present cpu not spinning

I pulled up the possitive side of this cap becasue it goes to ground even i pulled up and back in it goes to ground does this short?

[mcplslg123]

Re: LENOVO 320 turns on lights present cpu not spinning

If the cap was shorted, coil will also shorted to gnd.Since you measured 0.04K resistance, so cap was simply not shorted. It may have shorted now 'coz you applied heat to remove it. These sort of caps has a tendency to go short when heated-so you should replace it. You are simply getting lost in trobleshooting it. When laptop is turned on, try to measure voltage on all coils and see which rail(s) is not rising and focus on that part.

[mcplslg123]

Re: LENOVO 320 turns on lights present cpu not spinning

Better replace it with 330uf tantalum cap.

[String2016]

Re: LENOVO 320 turns on lights present cpu not spinning

@mclpslg123 , I have attached a photo the voltages on that area

[mcplslg123]

Re: LENOVO 320 turns on lights present cpu not spinning

Your problem is Vcore missing. What is the resistance on Pch Power coil(mostl likely the coil marked as 4R7 near batt connector. You need to check whether +3VS & +5VS is generated or not.

[String2016]

Re: LENOVO 320 turns on lights present cpu not spinning

resistance of the coil which mark 4r7 both sides have 17.99k when measuring it show 17.99 the goes to 0l both sides

[String2016]

Re: LENOVO 320 turns on lights present cpu not spinning

and the coil 4r7 has a voltage of 8.4v both sides

[mcplslg123]

Re: LENOVO 320 turns on lights present cpu not spinning

Then it is likely charging coil and not pch power.

[mcplslg123]

Re: LENOVO 320 turns on lights present cpu not spinning

You should check the basic signals like S5_ON,S4/S3_on, Sus,VR_ON,All sys pwrgood,pch power ok, ec rst Dram rst etc.

[String2016]

Re: LENOVO 320 turns on lights present cpu not spinning

@mcplslg123 i cannot find schematic on this attach photo near gpu coils measurement

[Stevedb]

Re: LENOVO 320 turns on lights present cpu not spinning

Which is your boardnumber?

[Stevedb]

Re: LENOVO 320 turns on lights present cpu not spinning

Try this:
https://www.badcaps.net/forum/showth...80#post1217080

[mcplslg123]

Re: LENOVO 320 turns on lights present cpu not spinning

Thanks @stevedb for the schematics. @mulong2019, since you have schematic, start measuring voltage .

[Stevedb]

Re: LENOVO 320 turns on lights present cpu not spinning

No problem

[stefanos_gr]

Re: LENOVO 320 turns on lights present cpu not spinning

Did you find the problem?

[azerkode]

Re: LENOVO 320 turns on lights present cpu not spinning

Did you find the problem? i have same problem