Troubleshooting: Lenovo Motherboard

[kiraro]

Re: Troubleshooting: Lenovo Motherboard

check PR329(47k) PR330(10k) PR331(10K) PR332(12K),after that check BQ24737_VDD voltage present on pin 1 of PR330 !!

[kiraro]

Re: Troubleshooting: Lenovo Motherboard

and voltage of both side of PR 330?

[DanFen]

Re: Troubleshooting: Lenovo Motherboard

Hi kiraro thanks for your help!

First of all, it's really difficult to find where these resistors are located. I hope I am tracing them correctly I managed to locate two of them, but not sure how I'm able to locate the others (most probably they are somewhere else on the board). I'm attaching a photo.



Based on the photo:

PR329: 47k
PR330: 10k (0V on both ends)
PR331: not sure where this is
PR332: not sure where this is

This is where BQ24737RGRR is:

check PR329(47k) PR330(10k) PR331(10K) PR332(12K),after that check BQ24737_VDD voltage present on pin 1 of PR330 !!

[kiraro]

Re: Troubleshooting: Lenovo Motherboard

REGN confirmed 6V. I don't have a DC Power Lab. Tempted to get one, only if I get better with this

... I'll get PQ302 out.

according to this you should get your 6v regn pin16 = BQ24737_VDD in the first side of pr330 (10k) and also you will get this voltage 3,2v (voltage divider : 6*(12/22) )on second side because also you said there is 0v on all pins of pq309 that mean gate pin 5 =0v so the voltage in the output of pr330 will not drop to zero( just will be dropped even gate get 0v in case of pq309 faulty )and you will get pacin voltage output ,if there is no voltage on pr330 trace the track to the pin 16

[DanFen]

Re: Troubleshooting: Lenovo Motherboard

Assuming that PR330 is actually the resistor I found, it has 0V in and out.

And correct, double checked PQ309, 0V on all pins.

It's going to be difficult to trace the components back to the IC. I can test out the components that seem to be on the track of pin 16 of the IC that are shown in the photo in my previous post.

according to this you should get your 6v regn pin16 = BQ24737_VDD in the first side of pr330 (10k) and also you will get this voltage 3,2v (voltage divider : 6*(12/22) )on second side because also you said there is 0v on all pins of pq309 that mean gate pin 5 =0v so the voltage in the output of pr330 will not drop to zero( just will be dropped even gate get 0v in case of pq309 faulty )and you will get pacin voltage output ,if there is no voltage on pr330 trace the track to the pin 16

[DanFen]

Re: Troubleshooting: Lenovo Motherboard

This is just a random check. Is a reading of 105 ohms on a resistor that has 100 on it normal. Shouldn't that be 10 ohms? This seems to be PR309.

[kiraro]

Re: Troubleshooting: Lenovo Motherboard

mesure resistance between pin 3 pq309b and regn pin16 = BQ24737_VDD?

[DanFen]

Re: Troubleshooting: Lenovo Motherboard

234 k ohms

mesure resistance between pin 3 pq309b and regn pin16 = BQ24737_VDD?

[kiraro]

Re: Troubleshooting: Lenovo Motherboard

that mean pr330 faulty or open , try to find it with continuity mode between pin 16 and resistance around pq309 ,and second side connected to pin 3 of pq309

[DanFen]

Re: Troubleshooting: Lenovo Motherboard

This is tricky for me. So if I understood correctly, if I switch to continuity mode, there should be beeping between PIN 16 BQ24737_VDD and PIN 33 PQ309B? If this is the case, then there is not.

that mean pr330 faulty or open , try to find it with continuity mode between pin 16 and resistance around pq309 ,and second side connected to pin 3 of pq309

[kiraro]

Re: Troubleshooting: Lenovo Motherboard

beeping with the first side of pr330 and the second side of pr330 beeping with pin3 pq309
pin16->first side pr330 beeping , second side pr330 -> pin3 pq309 beeping after find it measure her resistance that should be 10k if it's open or very hight value change it with another 10k resistance
when find pr330 try to find the second part of the voltage divider pr332 12k,first side beeping with pin3 pq309 and second side beeping with ground ,check value.

[DanFen]

Re: Troubleshooting: Lenovo Motherboard

thanks

So, continuity between:

PIN 3 PQ309 & PR330 first side = beep
PIN 3 PQ309 & PR330 second side = no beep
PIN 16 BQ24737_VDD & PR330 = no beep
Resistance on PR330 is 10k

I'll try to find PR332.

beeping with the first side of pr330 and the second side of pr330 beeping with pin3 pq309
pin16->first side pr330 beeping , second side pr330 -> pin3 pq309 beeping after find it measure her resistance that should be 10k if it's open or very hight value change it with another 10k resistance

[kiraro]

Re: Troubleshooting: Lenovo Motherboard

that should beeping between pin 16 and first side pr330 ,first or second side ,the important that should beeping at one of them and the other side should be beeping with pin 3 pq309

[kiraro]

Re: Troubleshooting: Lenovo Motherboard

don't confuse pr330 and pr331 ,they are two with same value 10k

[DanFen]

Re: Troubleshooting: Lenovo Motherboard

In this case it doesn't beep from PIN 16 to PR330.
First side of P330 beeps with PIN 3 PQ309.

PR332 is probably the resistor that is located just underneath PR330 in the photo I've posted earlier. You're right, it is 12K and the first side beeps with PIN 3 of PQ309 and the second beeps with ground.

that should beeping between pin 16 and first side pr330 ,first or second side ,the important that should beeping at one of them and the other side should be beeping with pin 3 pq309

[DanFen]

Re: Troubleshooting: Lenovo Motherboard

Very difficult to see, however the track is visible between PQ309 PIN 3 and a resistor, and I've concluded that it's PR330 (is it a good method to find components?). I am not sure where PR331 is.

don't confuse pr330 and pr331 ,they are two with same value 10k

[kiraro]

Re: Troubleshooting: Lenovo Motherboard

to verify it's pr330 or not :
pr331 is connected to pin 2 of QE2 (ACIN) If there is continuity to this pin so it's pr331, if not so it's pr330 ,best method it's with board view but sorry I don't have it .

in case it's pr330 and no continuity to pin 16 that mean the track is bad and you should make a jumper from pin 16 ( don't solder directly to the pin, you can solder on the pin 2 of pd303 ) to pr330 (side that it's not connected to the pin 3 of pq309 ) , with this you will have pacin signal and your 19v will come out .

[DanFen]

Re: Troubleshooting: Lenovo Motherboard

This is even trickier than I thought, the pins on the Datasheet of QE2 are different than the numbers on the schematics! But I'll follow datasheet because it explains the pins on a picture.

There is continuity between PIN 2 QE2 (which according to datasheet is source) to what I think is PR331.
There is continuity between PIN 1 QE2 (which according to datasheet is ground) to what I think is PR330.

Boardview would have helped unfortunately I couldn't find it. Probably does not exist.

pr331 is connected to pin 2 of QE2 (ACIN) If there is continuity to this pin so it's pr331, if not so it's pr330 ,best method it's with board view but sorry I don't have it .

[kiraro]

Re: Troubleshooting: Lenovo Motherboard

This is even trickier than I thought, the pins on the Datasheet of QE2 are different than the numbers on the schematics! But I'll follow datasheet because it explains the pins on a picture.

There is continuity between PIN 2 QE2 (which according to datasheet is source) to what I think is PR331.
There is continuity between PIN 1 QE2 (which according to datasheet is ground) to what I think is PR330.

Boardview would have helped unfortunately I couldn't find it. Probably does not exist.

what about the fourth resistance below PR329 it's not pr330? (in your picture post 43# )

[DanFen]

Re: Troubleshooting: Lenovo Motherboard

Hmm, that is a possibility. It's also 10k. But that still has no continuity to PIN 16. An no continuity to QE2.

what about the fourth resistance below PR329 it's not pr330? (in your picture post 43# )