EL432/EL532 Lenovo Ideapad S340-15API

[breid]

Hello I have a Lenovo Ideapad S340-15API
with EL432/EL532 board on the test bench.Enable signal not present!
PU402(+5VALWP)=0V
PU402(+5VLP)=4,9V
PU401(+3VALWP)=0V
PU401(3VLP)=0V
PU401(5V_3V_EN)= Pin 9 =0V=MOhms
PU402(5V_3V_EN)= Pin 12 =0V=100kOhms
No shorted caps found in this area
PR409 4.7 I had to desolder it was burnt out and had 280 ohms
What can be the reason I find the error simply do you have any ideas?

[mon2]

Re: EL432/EL532 Lenovo Ideapad S340-15API "5 V _3V_EN" No Enable Signal "

As per the article in the sticky above by @Piernov - always check the 2 x DCin mosfets.

That is, the _EN for the ALWAYS ON rail is driven by the B+ power feed.

The B+ power feed is after the 2 x DCin mosfets so start with these entry mosfets.

Attach the proper power adapter. Then measure the voltage on each pin of the DCin mosfets.

Interested in the voltage to ground of:

drain (5-6-7-8) ; pick one of these
gate (4)
source (1-2-3) ; pick one of these

Post all measurements.

Repeat for the 2nd mosfet. Often, the 2nd mosfet leaks and causes all of these issues.

Start with the above.

[breid]

Re: EL432/EL532 Lenovo Ideapad S340-15API "5 V _3V_EN" No Enable Signal "

PQ712
Sorce=20V
Gate=25V
Drain=20V
PQ740
Sorce=20V
Gate=25V
Drain=20
all normal

[reformatt]

Re: EL432/EL532 Lenovo Ideapad S340-15API "5 V _3V_EN" No Enable Signal "

Hello I have a Lenovo Ideapad S340-15API
with EL432/EL532 board on the test bench.Enable signal not present!
PU402(+5VALWP)=0V
PU402(+5VLP)=4,9V
PU401(+3VALWP)=0V
PU401(3VLP)=0V
PU401(5V_3V_EN)= Pin 9 =0V=MOhms
PU402(5V_3V_EN)= Pin 12 =0V=100kOhms
No shorted caps found in this area
PR409 4.7 I had to desolder it was burnt out and had 280 ohms
What can be the reason I find the error simply do you have any ideas?

LDO voltage missing. The enables are from the EC so you are too far ahead. Troubleshoot the missing +3VLP voltage. Perhaps a short on this LDO rail, remember these only produce about 100ma before they shutdown. The 5V LDO is working, and the enable is common to both so must be an output issue. Hopefully not a shorted EC.

As for PR409, that doesn't make much sense since it only appears to be for transient suppression, unless the cap below was shorted I guess. Besides it seems to be a @ on the schematic (NOSTUFF) so double check that.

[breid]

Re: EL432/EL532 Lenovo Ideapad S340-15API "5 V _3V_EN" No Enable Signal "

Thanks for the answer and I think you are right I only have 256ohms on the +3VLP LDO circuit at +5VLP I have MOhms now I desoldered the EC and the resistance has normalized kOhms. Now I just have to see how to program the new one because these programmers are not that cheap

[reformatt]

Re: EL432/EL532 Lenovo Ideapad S340-15API "5 V _3V_EN" No Enable Signal "

Buy from a vendor who pre-programs then if you don't want to drop the cash on a SVOD etc.

[breid]

Re: EL432/EL532 Lenovo Ideapad S340-15API "5 V _3V_EN" No Enable Signal "

I'm trying this

https://www.youtube.com/watch?v=GQGH6yZuXCc&t=552s

[WTFRules!]

Re: EL432/EL532 Lenovo Ideapad S340-15API "5 V _3V_EN" No Enable Signal "

I'm trying this

https://www.youtube.com/watch?v=GQGH6yZuXCc&t=552s

Hi,

How did it end with the replacement of the EC IC? I have the same scenario where the KB9022Q D is burnt and I only have at hand the CH341 programmer, were you able to programm the KB9022Q C with the link you posted?

Thanks!

[WTFRules!]

Hi,

How did it end with the replacement of the EC IC? I have the same scenario where the KB9022Q D is burnt and I only have at hand the CH341 programmer, were you able to programm the KB9022Q C with the link you posted?

Thanks!

OK, I can confirm that with CH341B and NeoProgrammer (MAlware aside) the KB9022Q D is 100% programmable.
Hope this helps to anyone looking the same as I did.

Have a good one.