Lenovo Legion 5 Pro - NM-D601 REV1.0 Turns off with battery conected

[judamex]

I have a Lenovo Legion 5 Pro laptop - NM-D601 REV1.0 when I connect the battery it turns off after 5 minutes of use, if I don't connect the battery the laptop can keep working perfectly, I have already checked the charging voltages and they are fine, no I know if any mosfet is not working well, how can I know?

[mcplslg123]

Check resistor value on SRP/SRN line of charging IC.

[judamex]

Check resistor value on SRP/SRN line of charging IC.

i chek the value

Resistor value
PR5410 - SRP = 10 ohm
PR5416 - SRN = 10ohm
PR5413 - BATSRC = 10ohm

PR5410 TO GND (terminal RED to GND, BLACK to pin) pin 1= 16.89 kohm, pin2= 87.2kohm
PR5416 TO GND (terminal RED to GND, BLACK to pin) Pin 1 = 16.93 kohm, pin 2 = 86.8 kohm

[mcplslg123]

SRP/SRN communication is fine. Have you tried with another battery? Which charging IC is used?

[judamex]

SRP/SRN communication is fine. Have you tried with another battery? Which charging IC is used?

Yes, it seems to have good readings, the laptop is practically new, it came out of the box with that error, it uses the BQ24780S charging IC

[mon2]

Remove all power. No battery. Investigate the battery mosfet @ PQ5403.

Meter in resistance mode.

Measure the resistance (not diode mode) across this mosfet:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

Post each measurement. Checking for a low resistance which means the mosfet is leaking. Be sure to post the resistance and the units of measure (ohms; kohms; Mohms, etc.).

[judamex]

Remove all power. No battery. Investigate the battery mosfet @ PQ5403.

Meter in resistance mode.

Measure the resistance (not diode mode) across this mosfet:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

Post each measurement. Checking for a low resistance which means the mosfet is leaking. Be sure to post the resistance and the units of measure (ohms; kohms; Mohms, etc.).

OK the measurement of PQ5403 on ohms:

RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = 19.30 kohms
RED terminal to source (1-2-3), BLACK terminal to gate (4) = 115.4 kohms
RED terminal to gate (4), BLACK terminal to drain (5-6-7-8-) 1.1Mohms and up

[mon2]

For a mosfet, these are considered to be very low resistance measurements:

RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = 19.30 kohms
RED terminal to source (1-2-3), BLACK terminal to gate (4) = 115.4 kohms

Suggest to flux and remove this mosfet. Allow it to cool down on your work table. Then measure the mosfet part again while it is on your work bench. Confirm if the resistance remains this low. If yes, this part is considered to be defective and should be replaced by a known good device.

This is a very common N-channel mosfet that can be replaced by many others.

Part # AONS32314.pdf (aosmd.com)

[judamex]

For a mosfet, these are considered to be very low resistance measurements:



Suggest to flux and remove this mosfet. Allow it to cool down on your work table. Then measure the mosfet part again while it is on your work bench. Confirm if the resistance remains this low. If yes, this part is considered to be defective and should be replaced by a known good device.

This is a very common N-channel mosfet that can be replaced by many others.

Part # AONS32314.pdf (aosmd.com)

I already measured the mosfet outside the board and if their values changed:

RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = .952 Mohm
RED terminal to source (1-2-3), BLACK terminal to gate (4) = 4.93 Mohm


on the motherboard it maintains the same measurements

RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = 19.30 kohms
RED terminal to source (1-2-3), BLACK terminal to gate (4) = 115.4 kohms

[mon2]

This battery mosfet is fine but still leave it off the board for now.

Test the resistance across the other mosfets using the same method:

a) test PQ5404 and also PQ5406 (suspecting that only one of these are actually soldered on the board)
b) test PQ5407
c) test PQ5402 and PQ5401 - if not done already.

Someone is causing this event when the battery & power adapter are both connected to the board. No power & no battery during the resistance mode of checking.

[judamex]

This battery mosfet is fine but still leave it off the board for now.

Test the resistance across the other mosfets using the same method:

a) test PQ5404 and also PQ5406 (suspecting that only one of these are actually soldered on the board)
b) test PQ5407
c) test PQ5402 and PQ5401 - if not done already.

Someone is causing this event when the battery & power adapter are both connected to the board. No power & no battery during the resistance mode of checking.

I test out of the board

PQ5404
RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = 1.052 Mohms
RED terminal to source (1-2-3), BLACK terminal to gate (4) = 4.5 Mohms

PQ5406
RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = 1.080 Mohms
RED terminal to source (1-2-3), BLACK terminal to gate (4) = O.L (It does not give me any measurement, neither in Ohms nor in Diode, it opens the mosfet but it does not give me any measurement)

PQ5407
RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = 0.800 Mohm
RED terminal to source (1-2-3), BLACK terminal to gate (4) = O.L (It does not give me any measurement, neither in Ohms nor in Diode, it opens the mosfet but it does not give me any measurement)

test on the board

PQ5402
RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) =0.6 Mohm
RED terminal to source (1-2-3), BLACK terminal to gate (4) =1.1Mohm

PQ5401
RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = 0.6 Mohm
RED terminal to source (1-2-3), BLACK terminal to gate (4) = 1.1Mohm

[mon2]

Missing for each mosfet are the 3rd measurement:

gate (4) & drain (5-6-7-8)

[judamex]

Missing for each mosfet are the 3rd measurement:

gate (4) & drain (5-6-7-8)

Sorry i forget take this measurement

Out of the board (change the reading place to an isolated and clean place and the measurements changed)

PQ5404
RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = 1.052 Mohms
RED terminal to source (1-2-3), BLACK terminal to gate (4) = O.L It doesn't give me measurement even in diode mode
RED terminal to gate (4), BLACK terminal to drain (5-6-7-8-) = O.L It doesn't give me measurement even in diode mode

PQ5406
RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = 1.080 Mohms
RED terminal to source (1-2-3), BLACK terminal to gate (4) = O.L
RED terminal to gate (4), BLACK terminal to drain (5-6-7-8-) = O.L It doesn't give me measurement even in diode mode

PQ5407
RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = 0.800 Mohm
RED terminal to source (1-2-3), BLACK terminal to gate (4) = O.L
RED terminal to gate (4), BLACK terminal to drain (5-6-7-8-) = O.L

test on the board

PQ5402
RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) =0.6 Mohm
RED terminal to source (1-2-3), BLACK terminal to gate (4) =1.1Mohm
RED terminal to gate (4), BLACK terminal to drain (5-6-7-8-) =O.L

PQ5401
RED terminal to source (1-2-3), BLACK terminal to drain (5-6-7-8) = 0.6 Mohm
RED terminal to source (1-2-3), BLACK terminal to gate (4) = 1.1Mohm
RED terminal to gate (4), BLACK terminal to drain (5-6-7-8-) =O.L

[judamex]

Missing for each mosfet are the 3rd measurement:

gate (4) & drain (5-6-7-8)

I'm starting to suspect the charging IC

[mon2]

If you have the tools and spare part available, worth the effort to test with a known good charging IC.

[judamex]

If you have the tools and spare part available, worth the effort to test with a known good charging IC.

I am going to replace the charger IC with one that I have in good condition, I will update if everything works

[judamex]

If you have the tools and spare part available, worth the effort to test with a known good charging IC.

UPDATE:

I replaced the 24780S charging IC with another one from a healthy device, and it did the same, it turned off after a little use with the battery connected, only with a charger it passed all the benchmarks

[mon2]

So it works only if the battery is disconnected with the power adapter as the only source?

Carefully, measure the voltage to ground of each pin on this charger IC with only the power adapter connected.

Then repeat with both, the power adapter and battery are connected.

Post all of your measurements. We may have to call in a priest but let us try this approach first.

[judamex]

So it works only if the battery is disconnected with the power adapter as the only source?

Carefully, measure the voltage to ground of each pin on this charger IC with only the power adapter connected.

Then repeat with both, the power adapter and battery are connected.

Post all of your measurements. We may have to call in a priest but let us try this approach first.

I performed the following measurements, noticing several details, such as that only with the battery connected the equipment stayed on for no more than 40 seconds.

Take 3 different measurements that appear in the table, only with charger (on), only with battery (off), and with battery+charger (On)

If any of these measures do not help me, I will have to call the priest himself.

[mon2]

Can you confirm the gate voltage of PQ5407 WITH battery & power adapter? It does not look right.



A few other points:

1) remove all power -> measure the resistance of the 4k resistor @ PR5405. Confirm this resistor matches the schematic value of 4k. Concern is that in your measurements, the CMSRC voltage to ground is lower than the power adapter voltage.

2) double check the BATTERY only measurement for pins 1 & 2 on the charger IC.

3) repeat the measurements WITH BATTERY & power adapter for pins 1 & 2 on the charger IC. Pin # 2 (ACP) should be a higher voltage than pin # 1 (ACN). In either case, the voltage measurements should be very close to each other. Note the voltage drop across ACP and ACN junction when using only the power adapter. Higher voltage difference when the battery is used or when both battery & power adapter is used.

With no power to the board and no battery, confirm the resistance from pin # 2 (ACP) directly on the charger IC to the current sense resistor @ PR5401. Then repeat the same test with pin # 1 to the same current sense resistor. Both checks should be ~0 ohms. Touch your meter probes together and this is the same resistance measurement you should have for this current sense resistor path.

Also, I think that for the BATTERY only, the pin # 19 measurement was missed in the above table. It should be the same voltage as pin # 20.