A2442 820-02098 Slow Charge, No Power on MagSafe Alone

Clever1

New member
Have an A2442 that suffered a lightning strike, unit would not power. Replaced 2 IC, UG400 and UG800; UG400 had a hole in it and UG800 had traces 2, 6, 10, 14,18 and 22 burnt off the board.

Repaired the traces under UG800 and replaced both IC, unit powers on now. MagSafe shows light and makes chime when plugged in, USB C makes chime when plugged in.

When on the login screen the battery doesn't show the charge icon when its on charger and it charges super slow. Left it over night and battery charged full.

Unit will not turn on with the battery unplugged and i don't have a extra battery to test with.

Measured the following without battery plugged in:
PPBUS_AON- 12.05v
PP3v8_AON- 3.8v
J5101
Pin 3- .65v
Pin 5- 0v
Pin 7- 0v
Pin 9- 0v
Pin 11- .45v

I mainly repair game consoles, but have a little experience with MacBook's, I'm just kind of stuck at where to look now.

Thank you for any help.
 

2informaticos

Administrator
Staff member
First of all, welcome to the forum!

Can you enter into macOS?
If yes, what you see on system report about battery?

Check resistance (ohm scale) over C5220/60.
Post Q5270 voltages.
 

Clever1

New member
Thank you for the response.

The OS has a password, i can ask to get it from them, they may not give it to me.

Q5270
PPVBAT_AON- 12.05v
SAVE_BAT_G- 4.41v
SAVE_BAT_S- 4.27v

C5220/60 20k ohm
Pin 1 of C5220 red to pin 1 of C5260 black 20k- just keeps going up
Pin 2 of C5220 red to pin 2 of C5260 black 20k- just keeps going up

measurements taken with no battery connected and board removed from the unit.
 
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2informaticos

Administrator
Staff member
"Check resistance (ohm scale) over C5220/60."
I meant between their pins!
As per schematic, you MUST get 2 ohm aprox.

You should get the password, to get more information from macOS about battery.
Also turn it on in diagnostic mode and see if any error pops up.
 

Clever1

New member
Oops, sorry about that. Both caps are reading ~3 using 200. Let me throw this thing back together and try to get it to boot into diagnostic mode. I was having trouble getting it to boot into anything other than the OS.
 

Clever1

New member
Diagnostics giving a PPP020, tried different power adaptors, magsafe and USB C. using 87W and 140W adaptors to test, original power adaptor not given to me when the unit came in.
 

2informaticos

Administrator
Staff member
All USB-C ports have the same behavior?

Post U5200's basic voltages, with charger alone (no battery): P_IN, AUX_DET, SMC_RST_IN, VDDA/P, EN_MVR, AUX_OK, A/BMON.
 

Clever1

New member
I only used the C port closest to the MagSafe to test during diagnostics. I may pull those out of the case and give them a visual inspection.

U5200
P_IN- 5.19v
AUX_DET-1.24v
SMC_RST_IN- .65v
VDDA/P- 5.05v/5.05v
EN_MVR- 5.05v
AUX_OK- 1.76v
A/BMON= 0v/0v
 

2informaticos

Administrator
Staff member
You may have another component, or trace damaged by lightning.
Mentioned chips are directly connected with CPU; it may be affected also.
 

Clever1

New member
Thank you, i will start around the areas that i repaired and take diode readings and double check everything.

All of those readings for U5200 are good? I am taking notes.
 

Clever1

New member
Unit is pulling 20v but no amps on all USBC, this thing is driving me crazy. Unit runs on the battery alone, which leads me to believe its not a bad battery, but i could be wrong.

Unit will not run on USBC alone, is this one of the types that need the battery plugged in to power? that what i am assuming.

Putting a meter on R5102 pin 1 PPDCIN_AON shows 0 volts, this should be 20v correct? DIODE shows .545 which on OpenBoard data shows normal. i will recheck the fuse for this line again but last time i checked was fine.

When the lid is closed it only pulls 5v and ~.90 amps and i hear a chime when i plug in the charger. Open the lid and it pulls 20v no amps and no chime, close the lid and it stays at 20v no amps, sometimes it will drop back to 5v and .9 amps.

The shop that i am working on this for is ordering a new battery just in case and to have in stock.
 

2informaticos

Administrator
Staff member
"PPDCIN_AON shows 0 volts"
Are you sure?
There must be at least 5V (before switching to 20V); no matters which USB-C, or Magsafe 3 port is connected.
 

Clever1

New member
Have my volt meter plugged into the charger port and lid closed and battery connected. shows 20v no amps, i am testing for voltage at pin 1 of R5102(no stuff) so just the pad and it shows 0 volts.

I am going to flip the board and leave the battery connected and see on another test point on the opposite side of the board.
 

Clever1

New member
I disconnected everything from the board and left the battery connected and flipped the board over and now the charge meter shows 5v and i get 5v on DCIN.
Tested on the fuses for the USBC ports.

There was a small amount of amp draw for about 3 seconds then it dropped back to 0 amps, but stays at 5v.
 

2informaticos

Administrator
Staff member
The board may not turn on with charger alone; not sure however.
But it should switch to 20V on USB-C ports with charger alone, for sure; valid for Magsafe 3 port also.
 

2informaticos

Administrator
Staff member
If machine still work with battery alone, your problem should be on input power areas.
Sometime, DFU restore can fix such kind of issue.

You've said in the starting post that booted with charger and slowly charging battery.
What happened since then?
 

Clever1

New member
No clue, i gave it back to the shop and he plugged the charger into the machine and it wasn't detecting the charger. He plugged a external drive into the port and it detected the external drive and could transfer data.

When the charger is plugged into the machine it doesn't change the icon to the charging icon.

Could this be the little board by the battery causing this?

I can run a time machine backup of the unit and try a DFU restore an see if that helps.
 

Clever1

New member
checking around the UG800 circuit since i replaced that chip, should i have 5v on RG830 pin 1(P5VUSBC23_EN_R)? or 5v on RG840 Pin 1 (UPC23_5v_EN?

I am getting ~12v on PPVIN_5VUSBC23_ISNS, since it say 5v in the line name am i correct to assume this should be 5v and not 12?

schematic says VOUT should be ~5v, i am not getting that voltage. What voltage is usually required on the enable line? is this just any voltage above 0?

Looking at the data sheet for UG840 i need to have VCC(1v8) on pin 6 pin 1 and 2 need voltage to output at pin 4(P5VUSBC23_EN_R) and this tells UG800 to turn on then i should have 5v on the output and this loops back into the chip on P5VUSBC23_PGOOD to tell the chip its good and PP5V_S2SW_USBC23 continues onto where it going?
 
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