820-2850 no s3 rails

[Chuck60]

At u7201
Ppbus_g3h=12.56v
Pp5v_s5 =5v
Pp3v3_s5 =3.3v

pp3v3s5_entrip1=800mv
Pp5vs3_entrip2=800mv
5vp3v3_reg_en=3.3v
Pp5vs3_vbst_r=5v
Pp5vs3_LL=0v

I’m seeing that both entrip signals are low so both s5 and s3 should be up. If I’m reading the schematic correctly. I have no short on s3 line. someone has already Been in this area and flux is all over it :/

 

[2informaticos]

We take our time to write correctly here (even capital letters for signal names); why don't you do the same, as first interested?

Post some history fault, sometime helps.

Check R/C7224 and all resistors/traces from 5V_S3 area.

 

[Chuck60]

Ok I will R/C7224 and all the traces.
History fault
MagSafe has dim green light.
PPBUS_G3H=12.56v
PP5V_S5 =5v
PP3V3_S3=3.3v
PP5_S3=0v
PP3v3_S3=0v
No fan spin. No shorts found on any of the above lines.

 

[2informaticos]

"PP3V3_S3=3.3v
------------
PP3v3_S3=0v"
Really?

Post again basic voltages for U7201, (when missing 5V_S3); pins 16, 13, 3, 8, 17, 6, 1.

 

[Chuck60]

No I’m sorry ? PP3v3_S3=0v my mistake.
I will take the the pin voltages when I get home but I definitely don’t have PP3v3_S3
Thank you

 

[2informaticos]

"PP3V3_S3=3.3v"
The mistake is this!
You probably meant PP3V3_S5...

 

[Chuck60]

Oddly I was double checking the voltages and the first time PPBUS_G3H=12.56v A few minutes ago and now I double checked it and it goes to 11.59 and slowly drains.

 

[2informaticos]

You must get stable 3V42_G3H and PPBUS_G3H too; without battery connected.
PPDCIN_G3H fluctuates too?

 

[Chuck60]

3V42_G3H=3.42v
PPBUS_G3H =11-7 but it doesn’t fluctuate it drains. I put probes on it. It goes to 11v then drians to 6-7v

PPDCIN_G3H= 16.71-16.30v fluctuating

 

[Chuck60]

ISL6259
Pins
17,18= 3.4 ohm
27,28 = 20.2 ohm

 

[2informaticos]

Post basic voltages for ISL 6259, especially when PPBUS_G3H drains; pins 1, 2, 3, 9, 12, 13, 14, 15, 17, 19, 20, 27.

 

[Chuck60]

ISL6259

1=15.05v
2=16.17v
3=4v
9=0v
12=3.41v
13=3.41v
14=3.2v
15=0v
17=7.62v
19=5.05v
20=5.07v
27=7.74v

Q7085 CHGR_AGATE_DIV= 15v I believe the issue is with my voltage divider shouldn’t it be 6.5v

 

[2informaticos]

There is no resistor divider, untill U7000 close it to ground.

Post R7080/81 and R7085/86 ohm values, measured onboard.

 

[Chuck60]

R7080=99.2k
R7081=61.4K

R7085=471k
R7085=330k

 

[2informaticos]

Q7080/85 look good.
PPDCIN_G3H is stable?
Just in case, replace U7000.

 

[Chuck60]

I replaced u7000 and I have the same issue
But I noticed the PPDCIN_G3H= 16.71-16.04v fluctuating again I’m thinking there must be a loose connection or bad solder Joint somewhere there also flux around the mage safe and fuse.