[SOLVED] 820-00138 A1398 not switch on after short from charger, what charger does it need?

[leonattpcs]

[SOLVED] 820-00138 A1398 not switch on after short from charger, what charger does it need?

Not switching on, owner says it was on until battery went flat, but now does not switch on or charge. I have a schematic for it, but no board view. Is there a board view anywhere for it? The schematic says it needs 20v, but I only have a normal 85w charger for MacBook Pro which is a lower voltage, so is there another type of MacBook Pro charger which is a higher voltage? When connecting what I have the light on it goes green then red as though it is charging so what gives?
Thanks

 

[aprendiz]

It should be an original 85W charger MagSafe 2....
voltage on PPBUS_G3H??
resistance between pins 17-18 and 27-28 from ISL6259???......

 

[leonattpcs]

How do I find the components on the board with no board view. There isn't a board view in the schematic either.

 

[aprendiz]

You can find the IC because it have a number over it and the distribution of the components around it is almost the same on every board... To find PPBUS_G3H, it is on pin 23 from ISL6259 or y any component attached to teh same line.....

 

[leonattpcs]

No Title

OK I will look for it. I have found the components on the board, the black beeps the green does not. Are they types of fuse?

 

[aprendiz]

Do you have a green light??? what voltage do you have on the green resistor with charger connected??

 

[leonattpcs]

When connecting power, you get green light that goes red, 16.75v on each side of the green component

 

[aprendiz]

Now read message #2 and answer...

 

[leonattpcs]

Checking isl soon then I will get back. I need to work out which pins are which from another schematic

 

[dukefawks]

First off get an ORIGINAL REAL 85W magsafe 2 charger. This thing will not power on from anything else.

 

[leonattpcs]

Damn, just realised the psu U was using was 65W,
Using 85W:
Light on connector goes green then red.
Voltage at the green component on each side goes between 16.1v and 16.85v.
On the assumption have got the correct pin 23 on the isl 6259 as high lighted in the attached picture the voltage goes between 1.65v and 1.66v

 

[2informaticos]

You didn't post resistance between pins 17/18 and 27/28 yet.
If OK, post voltages for ISL6259, like 2, 3, 19, 20, 1, 26, 9, 15.

 

[leonattpcs]

Will get resistances and voltages. Am I to assume I am correct from the picture about where pin 23 is?

 

[leonattpcs]

Pin 17-18 resistance 4.4 200 ohm setting

Pin 27-28 resistance .909 on 2k setting

Pin:

2 16.6v

3 3.9v

19 5.5v

20 5.51v

1 0v

26 0v

9 4.33v

15 0.5v

All voltages little bit up and down apart from pin 19 and 15

 

[leonattpcs]

I am thinking I need to look at Q7180, where abouts is it on the board?

 

[leonattpcs]

OK probably not gonna be able to as I have just found it after finding in on a 2013 MacBook Air board then found the same component on the MacBook Pro board

 

[dukefawks]

Look at schematic and tell me why there should be 20 Ohm between pins 27/28. You measured 4.4 between 17/18 which is probably OK, but should really be 2.2.
Also make sure your 85W charger is REAL! No China knock offs for testing!

 

[leonattpcs]

What an Engels idiot I am. I just answered the question and never thought about the answer. Ok so R7121 and R7122 and 10 Ohm each and looking at the schematic they are in series so adding them together, between pin 27 and 28 should give 20 Ohms. 0.909 is pretty much open circuit so something has burnt out. I say this as I am guessing R7120 has something to do with the circuit and probably burnt out unless a track is burnt out. I have guessed the location of R7121 and R7122 and am hopefully correct due to the readings I got. Where is R7120 though?

 

[2informaticos]

R7120 could be in the other side of the board; did you check?

 

[leonattpcs]

I have looked for the same component on a MacBook Air board 820 3437 and found it, looking for the same type of thing and not found it yet so still looking.