Ideapd 5 15ITL05 wont charge battery

[korsar86]

Looks ok. Attach only the battery. Then measure the voltage to ground of the battery. Next, measure the voltage to ground on each leg of the DCin mosfets. No power adapter should be connected. What are the voltages on the source / drain / gate pins of the DCin mosfets? Checking if there is a leakage here.

voltage to ground of the battery - 14.7V
voltage to ground on each leg of the DCin mosfets - 0V

[mon2]

Ok.

Which DCin mosfets were replaced? PQ301 & PQ302 are both suspects.

I would expect the same voltage to be present on pin 32 as pin 23 on the charger IC. When you disconnect the battery - do you see around 9v on pin 23? With the battery, the voltage drops to ~5v?

[korsar86]

I replaced PQ100, PQ106, and PQ304.
With the battery, on contacts 23 and 32, about 5V appears at first, then drops to 0.67V.

The board automatically turned on from the battery, on the type-c tester - 5V.



ps
Before that, I took measurements with another battery that turned out to have no charge at all.
I took measurements at contacts 23 and 32 with a charged battery.

[korsar86]

I’m stuck with this board and can’t figure out what this thing wants.
I replaced PQ301 & PQ302 as well as the BQ25710 charger IC - no change.

The board also has another connector labeled JDCIN1, although the laptop chassis doesn’t have an opening for it (so it’s apparently not used for charging in this model).
However, when I connect power through JDCIN1, Windows shows the charging icon with the lightning bolt, but it says “Plugged in, not charging.”
On the lab power supply, current draw is about 1.2A.

Below are my voltage readings on the BQ25710 with the battery connected and power supplied through JDCIN1 (laptop is turned on):

1 vbus - 19
2 ACN - 19
3 ACP - 19
4 chrg_ok - 3.25
5 OTG - 0V
6 ILIM - 2.15V
7 VDDA - 6V
8 IADPT - 0.46V
9 IBAT - 0
10 PSYS - 0.36V
11 PROCHOT - 1.01V
12 SDA - 3.2
13 SCL - 3.2
14 CMPIN - 0
15 CMPOUT - 0
16 comp1 - 1.35
17 COMP2 - 1.17
18 CELL_BATPRESZ - 4.5
19 SRN - 14.8
20 SRP - 14.8
21 BATDRV - 4.4
22 VSYS - 14.8
23 SW2 - 14.8
24 HIDRV2 - 19.3
25 BTST2 - 19.3
26 LODRV2 - 0
27 GND
28 REGN - 6.1
29 LODRV1 - 0.68
30 BTST1 - 20
31 HIDRV1 - 19
32 SW1 - 14.8

[mon2]

Confirm that pins 22 & 23 are not shorted to each other on the charger IC.

[korsar86]

Confirm that pins 22 & 23 are not shorted to each other on the charger IC.

No, these contacts are not shorted; I checked with a multimeter.

[mon2]

Have you tested with another known good battery?

[korsar86]

Have you tested with another known good battery?

I have two batteries, an old original one and a new one. Both behave the same way. Please tell me, does the multi-controller participate in charging the battery?

[korsar86]

Without the battery, the laptop negotiates 20V from the USB-C adapter and turns on normally. When the battery is connected, the voltage stays at 5V. But if I plug in the battery while the laptop is already running, it starts charging fine.

[mon2]

Is a 95W or higher power adapter being used to power this unit?