820-3492 no orange light

okay replaced u7000 and now have (due to a short on acok line)
SMC_BC_ACOK - 3.403
PP3V42 - 3.404
SYS_ONEWIRE -3.383
ADAPTER_SENSE - 3.383

still no green light
what am i missing?
 
PPBUS_G3H - starts at .9 and slowly drops to 0 over 30 min
SMC_RESET_L - 3.372
known good magsafe

i checked all resistors and filters on ppbus_G3H line and everthing checks out.
 
Last edited:

dukefawks

Administrator
Seems like there are multiple problems here, lets start with the obvious; 820-3492 is not a valid number...

Was this liquid? I suspect crap under SMC or dead SMC
 
820-3462.

there was liquid on keyboard but none on the board. i can replace the smc if you think thats causing the issue. give me a few days to get a donor board
 
Finally had time to mess with this board again. I reballed the smc and now have:

ppbus - 1.2v
SMC_BC_ACOK - 3.4v
PP3V42 - 3.4
SYS_ONEWIRE -3.38
ADAPTER_SENSE - 3.38v
 

larossmann

Administrator
Staff member
1) What is the resistance to ground on PPBUS_G3H?

2) What is the resistance between pins 17/18 on U7000? Measure at the pins. This should be around 2-3.

3) What is the resistance between pins 27/28 on U7000? Measure at the pins. This should be around 20.

4) What is the voltage on pin 2 of U7000? This should be charger voltage.
 
1- Black probe to ground - ..6Mohm
2- 17/18 - 3ohm
3- 27/28 - 20 ohm
4 - 16V

What do those four 17/18 27/28 do so i know for future use.
 
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larossmann

Administrator
Staff member
Do you have a green light with this now?

17/18 and 27/28 are part of the current sensing circuit. If it can't tell how much current the battery(27/28) and the charger(17/18) are using, it turns off the machine.

Those values read normally.

1) Are you getting a green light yet?
2) If you short pins 10 and 11 of U7000, do you get 12v on PPBUS_G3H?

This is all pointing to bad soldering around U7000 so far.
 
I've replaced the u7000 twice now. Once a while back and once yesterday. I'll check the values and let you know. I've triple checked to make sure soldering is good but still no green light though.
 
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larossmann

Administrator
Staff member
1) What voltage do you get on pin 1 of R7080?

2) What voltage do you get on pin 2 of R7080?

3) What voltage do you get on pin 1 of R7085?

4) What voltage do you get on pin 2 of R7085?

5) Does PPBUS_G3H go up if you remove F7040? What do you get on pin 1 of F7040 if you remove F7040?

All signs still point to badly soldered ISL6259 or bad ISL6259 from what I see.
 
okay for shits and giggles i replaced u7000 one more time. seems third time is the charm?

now i have ppbus voltage of 12.25, but still no light.

voltage of 7080 - 16.07 / 15.93
voltage of r7085 - 16.61 / 6.76

SMC_BC_ACOK - 3.4v
PP3V42 - 3.4
SYS_ONEWIRE -3.38
ADAPTER_SENSE - 3.38v
 
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larossmann

Administrator
Staff member
SMC is bad. Reflow to see if that fixes, if not then replace. 12.23v PPBUS_G3H means it is not communicating with the ISL6259. When the SMC is communicating with the ISL6259 PPBUS_G3H will be 12.56v. The SMC is also responsible for the green light, as SYS_ONEWIRE is the data line upon which it talks to the battery.
 

larossmann

Administrator
Staff member
Reballing the existing bad SMC will not fix it, it is like kicking a dead employee and asking him to work. Get a new SMC, the same way if your employee died you would find a new one..
 
Okay sorry for bringing this back from the dead but i finally had a moment to install new smc. Now have:

PPBUS_g3h - 12.56
SMC_BC_ACOK - 3.372
PP3V42 - 3.404
SYS_ONEWIRE -3.383
ADAPTER_SENSE - 3.383

I also noticed that TP[1]DCINVSENS_EN_L was gone so I ran a wire from q5480 to r5481. do i need to run it anywhere else?

I still have no fan spin :(
 

JohnB8812

New member
Ok so you made some progress! Voltage on PPVRTC_G3H, PP5v_S5, PP3v3_S5, and PP5v_S4? Check you rails in order like normal to see what is missing.
 
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