Lenovo G50-70 ACLU1/ACLu2 NM-A271 Rev. 1.0 no power

[Funkwarrior]

Re: Lenovo G50-70 ACLU1/ACLu2 NM-A271 Rev. 1.0 no power

Thanks again @piernov, really.

The datasheet of BQ I reading was wrong, sorry. (Why the BQ24737 datasheet is impossible to find?).

These are the values according to pin output of the board schematics.

I need to desolder PQ301 and PQ302 to test the Drain and Source, right?

Thanks again!

PU301 - BQ24737

1 ACN 20.3
2 ACP 20.3
3 CMPOUT 0.1
4 CMPIN 0.1
5 ACOK 0.1
6 ACDET 0.4
7 IOUT 0
8 SDA 0
9 SCL 0
10 ILIM 0
11 BM# 12
12 SRN 20.3
13 SRP 20.2
14 GND 0
15 LODRV 0
16 REGN 1
17 BTST 19.8
18 HIDRV 19.9
19 PHASE 20.3
20 VCC 20.3

[piernov]

Re: Lenovo G50-70 ACLU1/ACLu2 NM-A271 Rev. 1.0 no power

Yeah there is definitely an issue with PU301.
Measurements on post #17 were actually better.

SRN/SRP/HIDRV/PHASE all being around 20V means that B+ is shorted with BATT+, either due to bad PU301 (or bad soldering), or bad PQ309. Don't plug the battery in in this state, it will not like having 20V directly across it.

ACDET should be 2.6V. If ACDET is lower, then ACOK should not be 0V (but it is).

1V on REGN is wrong as well (probably causing the issue on ACOK). It should be 0 when ACDET is low (that's the case here), and 6V in normal operation. Again, bad PU301.

The resistance between drain and source of PQ301/PQ302/PQ303/PQ309 can be tested in circuit.

[Funkwarrior]

Re: Lenovo G50-70 ACLU1/ACLu2 NM-A271 Rev. 1.0 no power

Tested all PQ with Multimeter on circuit:
All with Positive lead on Source and negative lead on Drain in Diode mode gives me Resistance between 0.555 and 0.571 expect PQ309 with high resistance. So I took it off board and tested: Resistance 0.580.
I have also a short between on pin 1 and 2 onboard with PU301 offboard.
Now i will reinstall PQ309 e retest it onboard.
New BQ24737 arrived. I have to worry about the PIN1 and PIN2 short or I can install BQ24737 and test values again?
I hope I don't mess up the board...
Thanks

[piernov]

Re: Lenovo G50-70 ACLU1/ACLu2 NM-A271 Rev. 1.0 no power

Low resistance between pin 1 and pin 2 of BQ24737 is expected. they are connected to PR301, a current sense resistor that is only 0.01 ohm.

[Funkwarrior]

Re: Lenovo G50-70 ACLU1/ACLu2 NM-A271 Rev. 1.0 no power

Sorry @piernov, but I think I fried the board... I need more experience with this kind of soldering.
Thank you, I really appreciate your help.

[Funkwarrior]

Re: Lenovo G50-70 ACLU1/ACLu2 NM-A271 Rev. 1.0 no power

Change of mind, in the next days will try to understand what I've done..

[Funkwarrior]

Re: Lenovo G50-70 ACLU1/ACLu2 NM-A271 Rev. 1.0 no power

Hello, I resume this thread, hopefully to resolve this problem.
I resoldered with better tools the PU301 and now I have this values using an original Thinkpad 45w power supply :
PU301
1 ACN 20,70
2 ACP 20,7
3 CMPOUT 0
4 CMPIN 0
5 ACOK 0
6 ACDET 2,7
7 IOUT 0
8 SDA 0
9 SCL 0
10 ILIM 0
11 BM# 0
12 SRN 1,9
13 SRP 1,9
14 GND 0
15 LODRV 0
16 REGN 6,1
17 BTST 5,9
18 HIDRV 1,9
19 PHASE 1,9
20 VCC 20,7

PQ301
1 S 20,7
2 S 20,7
3 S 20,7
4 G 5,1
5 D 20,7
6 D 20,7
7 D 20,7
8 D 20,7

PQ302
1 S 20,7
2 S 20,7
3 S 20,7
4 G 5,1
5 D 20,7
6 D 20,7
7 D 20,7
8 D 20,7

ADAPTER_ID pin is 0V, even on the power socket :?

I understand now maybe the values on PU301 are OK, except for SDA and SCL...
Maybe I have IT8586E burnt?

[piernov]

Re: Lenovo G50-70 ACLU1/ACLu2 NM-A271 Rev. 1.0 no power

Ok so charger IC circuit is perfectly good now.
SDA and SCL are 0V most likely because +3VALW is missing. +3VALW may be missing due to missing EC_ON.
First make sure you have +3VLP.
If +3VLP is present but not EC_ON, maybe EC_ON is missing due to bad EC or bad EC firmware, but I'm not sure what are the requirements for EC_ON.

[Funkwarrior]

Re: Lenovo G50-70 ACLU1/ACLu2 NM-A271 Rev. 1.0 no power

I got 3,65V on +3VLP, tested on PJ304 Jumper. No EC_ON and no +3VALW.
So now I hope it's only the EC to change: it's the safest and quicker way to solve, right?
I don't think I will buy a programmer just for this chip...
Thanks piernov!

[boussaa islem]

Re: Lenovo G50-70 ACLU1/ACLu2 NM-A271 Rev. 1.0 no power

i have problems . my
Lenovo G50-70 ACLU1-ACLU2 NM-A271 REV-1.0 not affiched
i try flashing but the same problems