Dell 15 5570 LA-F115P wont start after it was repaired

[Bogdan Kolybaba]

Hi All. I had a problem with Dell 5570 : loose DC Jack and no battery charge from AC adapter althought laptop works normally and charging of the battery using USB3 was ok as well.
I have replaced DC jack, removed the blown TVS diode PD1 (didn't install the new one as don't have for now) and replaced PR6 and PR3. After AC adapter was connected to the MB, the LED was lighting as charging works (wite long flash after dim and again White ), after the light changed to the yellow. I thought it is ok now, assembled all back but after connected AC adapter - the fan had moved slightly and laptop wont start anymore. LED is not lit as well . Will trace the DC line for now. Any help will be appreciated - may be some fuse on MB? This is wifes laptop - so i am in big trouble now

[SMDFlea]

Please post a link to the schematic if it is already posted in the "Schematic requests ONLY!" sub forum.

Reminder: rules and organization of this section - https://www.badcaps.net/forum/troubl...f-this-section

[mon2]

Very very carefully, confirm the voltage to ground on PUB01 charger IC for:

ACIN_CHG
ACOK_CHG
DCIN_CHG

[Bogdan Kolybaba]

Sorry - thought i had added schematic and board view:

Schematic & Boardview: https://www.badcaps.net/forum/troubl...115p-boardview


Also, have attached the scheme where i highlighted concerned components in my post above

[Bogdan Kolybaba]

Hi Mon2!

Very very carefully, confirm the voltage to ground on PUB01 charger IC for:

ACIN_CHG = 0
ACOK_CHG = 60.8mV
DCIN_CHG = 0

with and w/o battery connected
DC_IN presents = 19.6v

BTW V_Batt shows 12.5V

[Bogdan Kolybaba]

Friends - what component is this (PL511 / 5A_Z150_1210_2P-NPM on BV)PJP 301 / JUMP_43X39. No signal 5V on it . Can't find in the internet either.

[mon2]

Re: PL511 - if any component has a '@' symbol in front of the part value (ie. prefix), then this part is NOT STUFFED. PCB design engineers will often layout out multiple component footprints to allow for testing and respectively bypassing the need for some parts for the live production run. Either to save on the bill of materials costs and/or in case there is a component shortage. For this specific case, you should see a solder blob on the PCB traces somewhere that is what is present instead of the referenced inductor / coil @ PL511. Also, the voltage here to ground should be ~19 volts if all is well.

See below. Confirm the voltages to ground (very carefully) for the following:

Expecting +DC_IN to be present since this is the raw power adapter voltage of ~19 volts.

So meter in DC volts scale of 20v or higher. Red meter probe to pin to test; black meter probe to ground.

Check:

red probe to pin 1-2-3 ; either one of these pins is ok on the mosfet @ PQ3. This is a 8 pin mosfet with a black body; 4 pins on each side. Locate the dimple / dot on the top side of the part = pin #1. Count the pins in a 'U' pattern where it will be top left = #1, #2 (below it), #3, #4 then other side going counter-clockwise #5, #6, #7, #8.

Pins 1-2-3 are tied together. Pin #4 by itself. Pins 5-6-7-8 are tied together - all to sink higher currents.

[Bogdan Kolybaba]

Re: PL511 - if any component has a '@' symbol in front of the part value (ie. prefix), then this part is NOT STUFFED. PCB design engineers will often layout out multiple component footprints to allow for testing and respectively bypassing the need for some parts for the live production run. Either to save on the bill of materials costs and/or in case there is a component shortage. For this specific case, you should see a solder blob on the PCB traces somewhere that is what is present instead of the referenced inductor/coil @ PL511. Also, the voltage here to ground should be ~19 volts if all is well.

See below. Confirm the voltages to ground (very carefully) for the following:

Expecting +DC_IN to be present since this is the raw power adapter voltage of ~19 volts.

So meter in DC volts scale of 20v or higher. Red meter probe to pin to test; black meter probe to ground.

Check:

red probe to pin 1-2-3 ; either one of these pins is ok on the mosfet @ PQ3. This is a 8 pin mosfet with a black body; 4 pins on each side. Locate the dimple / dot on the top side of the part = pin #1. Count the pins in a 'U' pattern where it will be top left = #1, #2 (below it), #3, #4 then other side going counter-clockwise #5, #6, #7, #8.

Pins 1-2-3 are tied together. Pin #4 by itself. Pins 5-6-7-8 are tied together - all to sink higher currents.

All 1,2,3 are 19.6V, No fluctuation. Thank you for detailed description of the procedure, I am using the Board View, although there are some minor difference from my MB but still ok.

Regarding PL511, on the board, it looks like a ceramic capacitor. According to the power diagram it is smth like dc/dc - but I doubt . Never seen DC/DC like this before.

[mcplslg123]

PU1,pin5 -voltage present?

[Bogdan Kolybaba]

PU1,pin5 -voltage present?

PU1:
PIN # 1 = 19.2V
PIN # 4 = 2.4V
PIN # 5 = 3V



Added later....

I have on PU 501 :
1 =2.6V
2=3=4=5=12.3V
6=0v
9=0v
11=2.4v
15=4.6v
16=17=3v

PJP501=PLL511=12.3v (19VB on BW???)
PJP503=0V

PJP301 =12.3v

PU301:

Pin 12 (EN_3V)=0V

[Bogdan Kolybaba]

Additionally to the above:
I have on PU 501 :
1 =2.6V
2=3=4=5=12.3V <--------------Why it is 12, Not 19V??? Cant understand why the voltage drops. See attached.
6=0v
9=0v
11=2.4v
15=4.6v
16=17=3v

19V = 0 , <-------------------Should be +5VALWP

[Bogdan Kolybaba]

Hi . Found a burned PDB03 diode, so +DC_IN_SS 19v looks disconnected. Just have questions: +VBUS_DC_SS and +19VB derives from +DC_IN_SS - why do they come back together?

[Bogdan Kolybaba]

Very very carefully, confirm the voltage to ground on PUB01 charger IC for:

ACIN_CHG
ACOK_CHG
DCIN_CHG

Now i have

ACIN_CHG = 3.6
ACOK_CHG = 3.06
DCIN_CH = 19.4

Still no light on MB led

[mon2]

When diodes are stitched together like your previous post - the power supplies are being "OR'd" in the logic term sense. That is, if either of the power feeds from the backside (aka anode) of the diode is present, then that voltage will travel in the direction of the arrow head onto the cathode. Even better is that even if multiple power rails are present, only the highest voltage will reach the cathode without harm to the other voltage rails. As long as the diode is working, no one gets hurt. You cannot just tie multiple different potentials of voltages together without such protection. This is a low cost way to OR the power rails.

[Bogdan Kolybaba]

Unfortunately changing the burned Schottky doesn't help. I am still looking for a solution. As I understand, i should concentrate on the following rails, as they are always on in any states (see attached):

+3VALW - - System +3VALW always on power rail;
+3VLP - - +19VB to +3VLP power rail for suspend power;
+5VALW - - System +5VALW power rail

Am I correct? I should not look for CPU or other power rails till those above arent in order, shouldn't I?

[Bogdan Kolybaba]

Update to above - I dont have neither +3VALW , +3VLP and +5VALW . Seems PU501 and PU301 is not generating them. Both IC have V_in +19VB = 12.6V (still don't know why not 19.6V, as concerned schottki is ok now). Where do i have to look for to get these IC generate +3 and +5

[mon2]

PU301 will output +3VALWP = +3VALW via PCB trace @ PJP302 if and only if (iff) EN1 enable signal (pin #12) is a logic '1'. EN2 signal is an enable for the LDO rail @ pin #17 = +3VLP.

Repeat the same review for PU501 with EN1 (pin #12).

[Bogdan Kolybaba]

PU301 will output +3VALWP = +3VALW via PCB trace @ PJP302 if and only if (iff) EN1 enable signal (pin #12) is a logic '1'. EN2 signal is an enable for the LDO rail @ pin #17 = +3VLP.

Repeat the same review for PU501 with EN1 (pin #12).

EN! is activated By EC , right? So I must look for EC supply and why it doesn't enable EN1. If EC burned - no sense to recover MB then. Can you suggest any methodic how to test EC please? IMHO supply goes from PU1 PIN # 5 = 3V 3.3V_ADP_DCIN, doesnt it? To make EC works i need just to supply +3VALW_EC to the VTR pins. Tomorrow will look to this. I see on scheme there another diode from 3.3V_ADP_DCIN to EC, it may be burned.

F##CK I thought that supply for this Amber/White LED doesnt involve EC, just through comparetors.

[mcplslg123]

+19VB = 12.6V This is correct as NVDC technology is used here in charging circuit. First pririty should be to get +3V LDO on pin17 of PU301(as this will power the EC). EN1 will come only when SIO is powered thru 3V LDO-so dont focus on EN1 now.
Check EN2 status on pu301 and resistance to GND on pin17,pu301(No power attached).

[Bogdan Kolybaba]

+19VB = 12.6V This is correct as NVDC technology is used here in charging circuit. First pririty should be to get +3V LDO on pin17 of PU301(as this will power the EC). EN1 will come only when SIO is powered thru 3V LDO-so dont focus on EN1 now.
Check EN2 status on pu301 and resistance to GND on pin17,pu301(No power attached).

It seems that Pin17 of PU301 generates +3VLP as per attached power diagram. Or i am mistaken? Unfortunately, I cant find datasheet neither for PU301 and Pu501 to findout next steps.

I have no signal on pin#17 of PU301, on the D1 Schottky i also have nothing on all pins. Resistance of Pin17 - GND is infinite.
But i have a 3.3V signal on PU501 pin#17 though.

I am confused now. May be I have to connect BIOS RealTime Clock Board to get +3 from there? But i remeber that Whie/Amber Led worked w/o this board connected.