Dell Precision 7510 charge battery and left side board problem.

[mon2]

Re: Dell Precision 7510 charge battery and left side board problem.

Also please confirm the MDV1524 is correct replacement for AON7752

Yes, the MDV1524 looks to be compatible. Same footprint, pinout and heavier current support. Vgs is very similar as well.

[Andreasbest]

Re: Dell Precision 7510 charge battery and left side board problem.

So PC114 was indeed grounded
Replaced PQ101
Now i have a problem with PQ103 traces on MB, they are all kinda shorted between them (~20Ω)
PQ103 is not soldered, i just measure the traces on it's position, is this normal?

Thank you for the confirmation.
My main problem is with PQ103, i removed it because was burnt too but all traces seems shortcircuit to each other, only 20Ω resistance.
Is this normal?

[mon2]

Re: Dell Precision 7510 charge battery and left side board problem.

Hi. Can you confirm that PQ103 is as per attached schematic ?

You have removed this part and are measuring 20 ohms between the pads for

GATE & SOURCE ?

GATE & DRAIN ?

SOURCE & DRAIN ?

If yes, lift up one leg on coil PL102 and measure again.

Post where exactly you are measuring the 20 ohms.

[Andreasbest]

Re: Dell Precision 7510 charge battery and left side board problem.

Hi. Can you confirm that PQ103 is as per attached schematic ?

You have removed this part and are measuring 20 ohms between the pads for

GATE & SOURCE ?

GATE & DRAIN ?

SOURCE & DRAIN ?

If yes, lift up one leg on coil PL102 and measure again.

Post where exactly you are measuring the 20 ohms.

Hello!
I removed PQ103 because DRAIN was shorted with GATE, then i notice that it's traces on MB are shorted/20Ω too.
I measured DRAIN with SOURCE, DRAIN with GATE and also DRAIN with GROUND, all of them are 20Ω.
Now with PL1L102 lifted i get:
DRAIN with SOURCE 0.8ΜΩ
DRAIN with GATE 0.8ΜΩ
DRAIN with GROUND 7.5MΩ

all measurements with BLACK probe on drain.

[mon2]

Re: Dell Precision 7510 charge battery and left side board problem.

With PL102 having 1 leg lifted, what is the resistance between pin # 2 (red meter lead) of PL102 pad and ground (BLACK meter lead) ?

[Andreasbest]

Re: Dell Precision 7510 charge battery and left side board problem.

With PL102 having 1 leg lifted, what is the resistance between pin # 2 (red meter lead) of PL102 pad and ground (BLACK meter lead) ?

Goodmorning!
~20Ω (18,9Ω precisely)

[Andreasbest]

Re: Dell Precision 7510 charge battery and left side board problem.

Bump

[Andreasbest]

Re: Dell Precision 7510 charge battery and left side board problem.

PL102 lifted and short circuit is gone, no more 20Ω but several kΩ instead.
Short still remains on lifted coil (red arrow short, green arrow no longer short)

[Spider1211]

Re: Dell Precision 7510 charge battery and left side board problem.

Remove PL102 completely. Which side is which? Green arrow is pin 1 or 2 (referring to schematic).

Is PJP102 and PJP103 present?

[SMDFlea]

Re: Dell Precision 7510 charge battery and left side board problem.

Remove PL102 completely. Which side is which? Green arrow is pin 1 or 2 (referring to schematic).

Is PJP102 and PJP103 present?

PJP102 and PJP103 are after pin 2 of PL102. +5VALWP -> +5VALW

[Andreasbest]

Re: Dell Precision 7510 charge battery and left side board problem.

Yes, side connected to PJP102 has 20Ω, the other is on ~300KΩ (with PL102 removed)

[Spider1211]

Re: Dell Precision 7510 charge battery and left side board problem.

What I meant was, is PJP102/3 solder or continuous copper track? If it is solder type, i'd suggest resoldering PL102 and removing the jumper. That way you can eliminate the chip itself as a potential cause and you could also test if the chip is working properly by powering the board (provided ofcourse that you took care of the shorted mosfets).

[Andreasbest]

Re: Dell Precision 7510 charge battery and left side board problem.

PJP102 and 103 are both solder jumpered.
I'll remove jumper solder from 102 on Monday that i'll return to bench and reply.
Also both burnt mosfet are replaced.
After pjp102 opening can i try to power on the mb provided the 20Ω resistance is limited to the one pin of pjp102?

[Spider1211]

Re: Dell Precision 7510 charge battery and left side board problem.

Just to confirm, do you still get 20Ohm after removing daughter boards? If you havent tried, try that first.

You need to remove solder on both pjp102 and pjp103. After that measure resistance again, the pjp pad connecting to PL102 should be high resistance and the other pad should still be 20Ohms.

If thats the case, then yes you can apply power and try turning on the laptop. You should read 5V on PL102. Otherwise report back on the resistance values you get.

[Andreasbest]

Re: Dell Precision 7510 charge battery and left side board problem.

Yes, bot daughterboards are disconnected, only GPU is still attached.
Ok will do this first thing Monday morning and report back.

[Andreasbest]

Re: Dell Precision 7510 charge battery and left side board problem.

Just to confirm, do you still get 20Ohm after removing daughter boards? If you havent tried, try that first.

You need to remove solder on both pjp102 and pjp103. After that measure resistance again, the pjp pad connecting to PL102 should be high resistance and the other pad should still be 20Ohms.

If thats the case, then yes you can apply power and try turning on the laptop. You should read 5V on PL102. Otherwise report back on the resistance values you get.

Goodmorning, back to the bench again.
I work around PL102 and got some strange readings.
With PL102 unsoldered i have 20Ω in upper pin (the one connected directly to pjp 102 and pjp103) and the same time on both pins of both pjp jumpers that i desolder!
With a few words, everything above PL102 upper pin is 20Ω to GND.

[Andreasbest]

Re: Dell Precision 7510 charge battery and left side board problem.

bump

[Spider1211]

Re: Dell Precision 7510 charge battery and left side board problem.

Try removing PU101 to and measure resistance again (DO NOT power motherboard with this chip removed). If its still same, try removing PU1001 (CD3301) since you had an almost similar reading last time. Report back after trying.

Aalso measure resistance on all coils and post your resistance reading.

[Andreasbest]

Re: Dell Precision 7510 charge battery and left side board problem.

Should i remove PU101 first and then check resistance on coils OR coils first?

[Spider1211]

Re: Dell Precision 7510 charge battery and left side board problem.

Since you mentioned desoldering PJP102/3 doesn't change anything I'd start with pu101 first.