pavilion 15 Y11A motherboard low ACDRV signal

[Zilicon]

Greetings...
Please, I need help in fixing the above board problem. The board number is DAY11AMB6E0 REV: E.

0.8V is the voltage that was able to deliver into the system due to ACDRV being stuck at 0.8V. The system works when 19V is introduced to the PQ20 drain, but the battery does not charge.

Below is the IC's reading when plugged in:

1. 0.8
2. 0.8
3. 0.8
4. 0.8
5. 0
6. 1.6
7. 0.4
8. 0.5
9. 0.5
10. 0
11. 1.9
12. 1
13. 1
14. GND
15. 0
16. 6
17. 5.9
18. 0
19. 1
20. 19.7

There is no break between PR 211, 137 and the IC.

Attached is the schematics diagram of the charging IC: BQ24738H

[mon2]

Re: pavilion 15 Y11A motherboard low ACDRV signal

Remove all power -> remove PR22 off the logic board. Do not lose this 4k resistor.

Power up again and check the voltage to ground of ACDRV pin of the charger IC. Measure directly at the charger IC pin.

Post the measurement.

[Zilicon]

Re: pavilion 15 Y11A motherboard low ACDRV signal

The measurement is 0.8V

[mon2]

Re: pavilion 15 Y11A motherboard low ACDRV signal

Measure the voltage on each side of PR16.

[mon2]

Re: pavilion 15 Y11A motherboard low ACDRV signal

Fault in this area. This threshold voltage must be > 2v4 for the charger IC to detect the adapter. Then the ACDRV boosted voltage will follow.

Remove all power. Meter in resistance mode.

Measure the resistance of each resistor @ PR16 and PR213.

Post each measurement.

[Zilicon]

Re: pavilion 15 Y11A motherboard low ACDRV signal

the voltage on PR16 resistor: 19.7 and 1.6

[mon2]

Re: pavilion 15 Y11A motherboard low ACDRV signal

The final lower voltage @ 1v6 is not the correct voltage for ACDET. It should be higher and must be greater than 2v4 for the charger IC to detect a valid power adapter.

Remove all power. Meter in resistance mode. Check the resistance of:

PR16
PR213

Meter probes across each resistor to measure.

One of these resistors is not the correct value and causing the lower ACDET voltage.

[Zilicon]

Re: pavilion 15 Y11A motherboard low ACDRV signal

The resistance of
PR16: 499k, 69.9k
PR213: 0, 69.9k

[mon2]

Re: pavilion 15 Y11A motherboard low ACDRV signal

I am not sure I am following the measurement readings.

Meter in resistance mode. No power to the logic board.

One meter probe to one pin of PR213; other meter probe to other pin on PR213.

Repeat for the other resistor.

Post the measurement. If you see '1' = over limit, then switch to a higher resistance scale on the meter. If you have an auto adjusting meter, then it is ok as-is.

[mon2]

Re: pavilion 15 Y11A motherboard low ACDRV signal

Wait - is the battery connected? If yes, please remove it and measure again.

[Zilicon]

Re: pavilion 15 Y11A motherboard low ACDRV signal

PR16: 430k, 230k (sometimes it will read 450k, 400k)
PR213: 69.9k, 67k

the above measurement was taken directly from the resistors, probes were swapped for readings. hat explains the double double readings. while previous readings taken was done with the com probe in ground.

[Zilicon]

Re: pavilion 15 Y11A motherboard low ACDRV signal

The resistance of
PR16: 499k, 69.9k
PR213: 0, 69.9k

These were taken with the com probe in the ground.
No battery or power on the system

[mon2]

Re: pavilion 15 Y11A motherboard low ACDRV signal

Ok. Carefully flux and remove resistor PR17 off the logic board. Do not lose this part.

We want to remove this part from the equation to see if the ACDET value changes.

Then power up with the adapter and check the voltage again @ ACDET pin.

Based on the resistor voltage divider calculator, if you have ~19v as input to PR16 and if the resistors are with a stable resistance, the voltage should be ~2v66 at ACDET.

It should not be 1v6. That is too low. If you still have this low voltage then recommend to replace at least PR16.

If you do not have these resistor values, we can try to work out with other values.

[Zilicon]

Re: pavilion 15 Y11A motherboard low ACDRV signal

The ACDET changed.
it increases to 2.7V ACIN on pin no 5 now has a voltage, 2.9V at PR217

[mon2]

Re: pavilion 15 Y11A motherboard low ACDRV signal

Very good -> check the ACDRV pin now.

[Zilicon]

Re: pavilion 15 Y11A motherboard low ACDRV signal

the ACDRV remains at 0.8V. it remains the same after PR22 removal.

[mon2]

Re: pavilion 15 Y11A motherboard low ACDRV signal

What is the voltage to ground @ ACDET pin # 6 of the charger IC ?

[Zilicon]

Re: pavilion 15 Y11A motherboard low ACDRV signal

@ACDET pin has 2.7V after PR17 was removed.

[mon2]

Re: pavilion 15 Y11A motherboard low ACDRV signal

Post a fresh list of measurements of the charger IC.

At this point ACDRV should return to ~25v so the charger IC may be defective and needs to be replaced but let us review your new list.

[Zilicon]

Re: pavilion 15 Y11A motherboard low ACDRV signal

Thank you so much @mon2, I just had it resolved now. thank you a million times.

what happened was that PQ35 pin 1 which is GND was absent. Hence, there was voltage at the pin, and pin 3. so I created a ground for the pin. That solves the problem.

thank you so very much.