Lenovo Yoga 500-14ISK - No battery charge

[nrcslim89]

Hello there, today I have an Lenovo Yoga 500-14ISK.
This laptop seems to have some issues far has I know from all over internet and here on forum, on battery charging but not have a direct solution or even a good solution that really works and stabilize the charging circuit.

OK, so has I said I'm facing a issue on board that not charge the battery at all.
The laptop works well with charger, but LCD start flicking when try to charge the battery.
When I remove battery lcd not flick and all goes fine.
But with battery no charge circle and level is always at 0%.

I already searched for the schematic but I don't found it yet.
Could anyone help me checking this issue?

[yoga500]

Re: Lenovo Yoga 500-14ISK - No battery charge

I have the same problem. has anybody an idea what we can do?
I bought a new battery and also a new power supply but does not help?

[mcplslg123]

Re: Lenovo Yoga 500-14ISK - No battery charge

Which charging ic it uses??

[teknikbursa]

Re: Lenovo Yoga 500-14ISK - No battery charge

find the resistor on image and change it with 10 ohm resistor

[nrcslim89]

Re: Lenovo Yoga 500-14ISK - No battery charge

find the resistor on image and change it with 10 ohm resistor

Thanks a lot, i will try to find and try to replace the resistor.
When i have new i will report.

Thanks for your tip.

[nrcslim89]

Re: Lenovo Yoga 500-14ISK - No battery charge

Hello i was try to find this IC to find resistence.
nut i don't have that IC, mine is BQ24780.

This could help you ?

[nrcslim89]

Re: Lenovo Yoga 500-14ISK - No battery charge

I found this IC NCP81382

And on datasheet the pins 12 until 18 (VSW - Switch Node Output) have connection to a big gray coil R15 and that coil goes to a 330 black capacitor, all checked on continuity mode and i get all a Beep to GND.
Should be fine ? or they are all in short ?

[mcplslg123]

Re: Lenovo Yoga 500-14ISK - No battery charge

NCP81382 is part of Vcore circuit-so the resistance should be low. Better you measure it in resistance mode(meter set at 200 ohm). If you get anything close to 004 or higher-its not likely a short. If the cpu is onboard you may get a even lower rating but should not be below 002.

[nrcslim89]

Re: Lenovo Yoga 500-14ISK - No battery charge

NCP81382 is part of Vcore circuit-so the resistance should be low. Better you measure it in resistance mode(meter set at 200 ohm). If you get anything close to 004 or higher-its not likely a short. If the cpu is onboard you may get a even lower rating but should not be below 002.

I will check.
Wich points hi have to verify?

[teknikbursa]

Re: Lenovo Yoga 500-14ISK - No battery charge

I know your ıc is bq 24780
follow the vcc pin of ıc and find the resistor

[mcplslg123]

Re: Lenovo Yoga 500-14ISK - No battery charge

@warenc, you started the thread saying charging issue-so i assume you are getting display but its not charging battery. Correct?? Then why you are probing vcore circuit?? You need to stay focussed and solve problem one by one. Start with charging IC Voltage measurement.

[nrcslim89]

Re: Lenovo Yoga 500-14ISK - No battery charge

@warenc, you started the thread saying charging issue-so i assume you are getting display but its not charging battery. Correct?? Then why you are probing vcore circuit?? You need to stay focussed and solve problem one by one. Start with charging IC Voltage measurement.

Yes problem is bad charging with flicker screen only.
I will verify the VCC rail of charger IC

[nrcslim89]

Re: Lenovo Yoga 500-14ISK - No battery charge

find the resistor on image and change it with 10 ohm resistor

Hello i follow the schematic of BQ24780 and check the VCC resistor and i find a anormal value and replace ir for 10Ohm resistor... guess what ??
I am happy to say you that you help me solving this case i think problem has been solved.
I am on charging test... but screen dont flick anymore.

[nrcslim89]

Re: Lenovo Yoga 500-14ISK - No battery charge

Motherboard and Issue solved with that resistor thanks a lot teknikbursa.
No flicking screen and battery charge well

[teknikbursa]

Re: Lenovo Yoga 500-14ISK - No battery charge

Motherboard and Issue solved with that resistor thanks a lot teknikbursa.
No flicking screen and battery charge well

Happy helping to solve problem.

[Rebeli]

Re: Lenovo Yoga 500-14ISK - No battery charge

Hello

I have the same issue but the VCC resistor is @ 10 Ohms. Is the BQ chip faulty?

[teknikbursa]

Re: Lenovo Yoga 500-14ISK - No battery charge

pls add again back what tou removed and Return back all you did.
and change the resistor on 20.th pin which is vcc pin. just upward of pc4406
İf that resistor is ok (10 Ohm) try to change BQ

[nouriassafi]

Re: Lenovo Yoga 500-14ISK - No battery charge

The above resistor keeps failing. Is this a design flaw?
I have replaced the above resistor three times, every two months, but the resistor keeps failing. Would it be safe just to short the resistor?

[emestee]

Re: Lenovo Yoga 500-14ISK - No battery charge

If this is really in the VCC circuit of the IC, then no, it is not safe to remove, as it is a current limiting resistor. And the underlying problem would be the IC pulling too much current. You could work around it by dropping in a higher wattage resistor but what you really need to check is whether something is drawing too much out of LDO and gate pins. If there isn't, might be a good time to replace the IC.

[matkauton]

Re: Lenovo Yoga 500-14ISK - No battery charge

Very useful theme. I will upload a picture with the exact resistor!