820-00840-01 not working with battery

[Biggtechman]

Macbook A1708
customer said..
it was working on battery then one day it wasnt.


i have replaced the battery with no fix.
funny thing is the macbook attempts to turn on after new battery is installed, but it comes up with charge me flashing on screen.
i plug in charger, it turns on..
battery has an x in it and in system reports it says no battery installed.

i have chacked
J6951, seems fine
Q7065, seems fine.
the only questionable thing i seen around J6951 was R6950, it reads 2769 in diode mode.
this reading was done with the daughter board disconnected.
could this be the problem?
thanks in advance for any advice

 

[2informaticos]

R6950 must be checked in ohm, 10K.
SYS_DETECT_L must be 0V, to enable the battery.

 

[Biggtechman]

thanks, I've tested it and it tests fine.
I've checked it with daughter board and battery connected.
I get it flactuating between. 02-.01v
I've also tested it was only daughter board, I get 0 with daughter board.
But when I screw the battery connector screw in it flactuates between .02-.01v
i check pin seven on the flex cable from daughter board, it reads 0.?
r6950 is on a ground pad.
Where would this .02v be coming from?

 

[Biggtechman]

work mentioning, with only the battery connecting the battery to the board.
I only get. 50v on ppvbat_g3h_conn
with the daughter board I get over 11v

i don't have a known good to use as a test point.

 

[2informaticos]

You must have the battery connected with the data flex and tightened screw.
0.01-0.02V is insignificant fluctuation; SYS_DETECT_L is good.
11V means the battery is enabled.
Is the same voltage on PPBUS_G3H with battery alone?
Do you get 3V3_G3H then?

Post voltage and diode mode on SCL/SDA lines of battery bus.
Should be good to test known good flex.

 

[Biggtechman]

OK.
so ppvbat_g3h_conn is reading 11.44v
ppbuss_g3h is also reading 11.44v
with battery alone ppvbat_g3h_conn only reads 1.5v and on ppbuss_g3h it reads 1.30v..
thats without battery data flex connected.
I've just noticed something strange.
ppvbat_g3h_conn is climbing slowly up and so is ppbuss_g3h. on about 1 minute they both clime around .20v bot there is a 20mv diffidence.
that's when battery data is not connected.
with battery alone I don't get any volts on 3v3_g3h, with data flex connected I get 11.44 same as reads on ppvbat_g3h_conn.

scl and sda lines on pin 2 and 3 of j6951 both read 3.40 but they both seem to flactuates between 3.30-3.40v

diode mode
j6951 pin 2 scl .449mv
j6951 pin 3 sda .449mv
ppvbat_g3h_conn .649mv
ppbuss_g3h .448mv

not sure if I mentioned this.
when I open the screen on battery the fan starts and backlight comes on. then it flashes the flat battery symbol..
as stated above in description, it runs on power but does not see battery.
Thanks again for your time.

 

[Biggtechman]

am ordered new bat data flex now.

 

[2informaticos]

I don't need any mention about battery voltage WITHOUT data flex; battery is not enabled without it.

Do you get 3V3_G3H on battery alone?
I mean when you get 11.44V on PPBUS_G3H, from battery.

 

[Biggtechman]

yes I get 11.44 on 3v3_g3h on battery alone.

 

[2informaticos]

"I get 11.44 on 3v3_g3h"
I don't believe you, really.
Half board should be fried...

Please, post accurate information.

 

[Biggtechman]

oops, sorry man. I mean 3.30v sorry.

 

[2informaticos]

You may have problems with SMC.
May need to reball it...

 

[Biggtechman]

what makes you say that?
why can't i just reflow it?
Sorry for giving wrong voltages on 3v3_g3h. it was late the night before and I sent the massage in the morning without thinking.
it was the correct voltage on 3v3_g3h.

if it helps...
When battery connected and I open the lid, it turns it on. but just goes to screen saying flat battery.

reballing smc is deficuilt, and from my understanding a last step.?

what is the name of the battery connected screw flex thing?
I'd like to order one.

 

[Biggtechman]

it works fine on power, just not battery.

 

[2informaticos]

You said battery is not recognized at all.
When SCL/SDA readings look good, usualy bad SMC.
So even reball may not help.

A simple reflow will not always resolder all the balls correctly...

 

[Biggtechman]

OK, so update...
I got anew flex for battery data, I noticed the battery screw metal flex had a bad crease.
I took it off and soldered the positive and negetive to the main board.
the system sees the battery now.

where can I buy a new battery screw metal flex from, what is it called?
eBay only showing data flex for battery.

 

[Biggtechman]

hello again.
Waiting on your response.
If you could please point me in the right direction to get the screw flex for main battery to mboard replaced.
I've checked ebay and a few other places.

or is it OK to just solder a high amp/volt wire to the positive and leave it like that?

 

[2informaticos]

Probably soldering direct wires is the only option.
Never faced with such problem.
However, even the power lines of battery are directly soldered on the MLB, no voltage comes there until data flex is connected.