E5570 la-c841p rev 3.0 - charger / battery issues

[Jdown79]

Hey guys, beginning to work on board level faults.
Machine is our stock, came in not charging batt. Battery is brand new, tested in another machine as not faulty. In Bios, originally it would say Battery: Health excellent, Charging: Idle, AC adaptor: Unknown
Using different genuine AC adaptors changed nothing.
Opening up showed liquid damage, PU1 was burnt out, and PR823 had rust on it.
Replaced PU1, no change. Replaced PR823, and the symptoms have changed.
Now battery shows as not installed, and AC adaptor : unknown.
I dont believe that either component is wrongly placed after staring at the board for however long.
What IC's are responsible for the detection of genuine chargers? I think thats my next port of call.
Thanks in advance.

[ktmmotocross]

Re: E5570 la-c841p rev 3.0 - charger / battery issues

post schematic

[Jdown79]

Re: E5570 la-c841p rev 3.0 - charger / battery issues

Aplogies, here we are.

https://www.badcaps.net/forum/showth...04#post1053304
.

[Techtiger]

Re: E5570 la-c841p rev 3.0 - charger / battery issues

whats is the voltage on all pins of Battery Connector with battrey inserted

PBAT_SMBCLK_C
PBAT_PRES#_C
PBAT_SMBDAT_C
+PBATT

[Vesko356]

Re: E5570 la-c841p rev 3.0 - charger / battery issues

Check resistance to ground in line NB_PSID first, then check continuity between NB_PSID and PS_ID. Are you sure PU1 is OK and is soldered correctly? You can unsolder PU1, and short pin3 to pin4 to check - if everything is OK (in the line) charger wattage must be detected in the BIOS, but furst check resistance to ground in NB_PSID line, there must be a reason for PU1 to burn (most probably someone is tried to power up the machine with HP adapter). If the resistance to ground is low in the NB_PSID line, check PD6 diode (most probably will be shorted).

[Jdown79]

Re: E5570 la-c841p rev 3.0 - charger / battery issues

PBAT_SMBCLK_C - 3.2-3.3v
PBAT_PRES#_C - 50mv
PBAT_SMBDAT_C - 3.2-3.3v
+PBATT - 11.8v

[Jdown79]

Re: E5570 la-c841p rev 3.0 - charger / battery issues

[B] check PD6 diode (most probably will be shorted).

Full disclosure, unaware if I'm testing the diode correctly, bare with me.
Third pin continuitity tests to ground, all 3 pins continuity test with each other.

EDIT:Seems to be alive, passing .8v

[Vesko356]

Re: E5570 la-c841p rev 3.0 - charger / battery issues

Full disclosure, unaware if I'm testing the diode correctly, bare with me.
Third pin continuitity tests to ground, all 3 pins continuity test with each other.

EDIT:Seems to be alive, passing .8v

What 8v??? What voltage are you talking about? It's a Dell not HP. It's a data signal line, one wire signal communication protocol line between the charger (Dallas/Maxim DS2501 chip) and the MEC5085 chip. PD6 is placed for protection against voltage in that line! Pin 2 and 3 are common and are connected to NB_PSID line, pin 1 is connected to dround! See the diagram! If it's a continuity between pin 1 and 2+3 NB_PSID line is shorted to ground, so the line is shorted or not? If the line is shorted you must replace PD6 (it's a ESD protection diode). Or you can remove it just for testing (but must be replaced later). After that charger wattage must be detected in the BIOS (if you soldered PU1 correctly, if not remove it and short pin3 to pin4). Simple as that.

[469896rammy]

Re: E5570 la-c841p rev 3.0 - charger / battery issues

replace pu1

[469896rammy]

Re: E5570 la-c841p rev 3.0 - charger / battery issues

voltages at pu1 pins

[wws911]

Re: E5570 la-c841p rev 3.0 - charger / battery issues

i had the same issue

on a bench supplu i used 16,5v the batery worked