SMC Issue on MBP 13 - Hardware Troubleshooting Guide

[macattack600]

Need info on where 5v rail comes from (No 5v on board)

I have shorted 2008 a1286 MBP 15" update- quit booting

PP5V_S0 =0v
PP5V_S3 =0v
I do however get some voltage from chip ISL6236 directly from some pins , am I supposed to be checking Out1 , Out1 or En1 ,En2?
or chip U7300 TPS51116

There is no water damage

I am having trouble locating the source of where my 5v starts or where it comes from I have schematic and boardview any pm or help a1286 early 2009 MBP 820-2330-A

 

[cpufixer]

I am having trouble locating the source of where my 5v starts or where it comes from I have schematic and boardview any pm or help a1286 early 2009 MBP 820-2330-A

check "power aliases" page, that should get you started. page 8, page 3.

 

[tiagobaracho]

Ok, I'll check.

I just did some measurements. what is this part, and are the voltages looking right or wrong. Is this feeding the 12vdc to battery? Or should it do so? Measurements were taken while mbp is running.

6.5v for the battery is too low... means 2,16 per cell... please check again the two pins... the first(GND and the last on the right (PPVBAT)... If you are really getting 6.5, you battery is probably dead...remember that those solder has a thing layer of varnish and sometimes you need to scratch to get a got measurement ....

 

[Wuchi]

6.5v for the battery is too low... means 2,16 per cell... please check again the two pins... the first(GND and the last on the right (PPVBAT)... If you are really getting 6.5, you battery is probably dead...remember that those solder has a thing layer of varnish and sometimes you need to scratch to get a got measurement ....

I measured it again and it is 6,5volts between first and last pins.
Tried another battery and it measured 7volts. I've not been able to charge these batteries, so I think that is the reason why the give so low voltages.

I disconnected the battery and measured voltage between first pin (GND) and the last pin on the right and it was 13,3volts. That's when the battery is disconnected.

Is there a problem on the batterysense line? The middle pin?

and thank you for helping!

 

[smithtony22]

Hi
did you ever manage to solve this issue? I have same board (820 3115). Been pulling my hair out trying to find what is the cause of this?

Hi guys i have an 820-3115 board here.
Bassicly the 16.5v DCin voltage fluctuates between 16v and 12v and no matter what i have tried nothing sorted it
Ive tried new Q7080 and new Q7085 but this didnt change, New U7000, Tested almost all the resistors around the U7000's area. Tested almost all the capacitors around the area.

I noticed lastnight when i have a charging IC installed i can hear a faint ticking coming from somewhere. My only guess is this is the source of the problem or why the voltage is fluctuating.


any thoughts would be apriciated

 

[cpufixer]

Hi
did you ever manage to solve this issue? I have same board (820 3115). Been pulling my hair out trying to find what is the cause of this?

check traces to isl6259 u7000,

 

[Wuchi]

6.5v for the battery is too low... means 2,16 per cell... please check again the two pins... the first(GND and the last on the right (PPVBAT)... If you are really getting 6.5, you battery is probably dead...remember that those solder has a thing layer of varnish and sometimes you need to scratch to get a got measurement ....

Here is some voltages around charger chip. Magsafe on and battery connected.

edit. and for additional info for everybody who wants to help: mid2010 mbp, doesn't charge, detects battery and tells cycles etc. works alone with battery, works with battery and magsafe, doesn't work with magsafe only (except smc bypass mode)

 

[tiagobaracho]

Here is some voltages around charger chip. Magsafe on and battery connected.

edit. and for additional info for everybody who wants to help: mid2010 mbp, doesn't charge, detects battery and tells cycles etc. works alone with battery, works with battery and magsafe, doesn't work with magsafe only (except smc bypass mode)

The only problem of this MCBP is that if you have disconnected the battery and try to use with magsafe it will not power on ? but on normal condition with battery and magsafe works normal ?

 

[Wuchi]

The only problem of this MCBP is that if you have disconnected the battery and try to use with magsafe it will not power on ? but on normal condition with battery and magsafe works normal ?

It doesn't charge the battery.

Edit: but yes, it will power up if magsafe and battery is connected. For now, six months ago it didn't even power up with magsafe.

 

[tiagobaracho]

It doesn't charge the battery.

Edit: but yes, it will power up if magsafe and battery is connected. For now, six months ago it didn't even power up with magsafe.

you will never be a 100% sure... you need to try..... check the gates lines for the fets... the fets itself... and if all checks out, change charge ic and the smc if not solved with the charge ic....
This is the best way to find a solution

 

[dellxps15]

ok, after big time, im still fighting with a macbook 820-2879. after change about 4 time u7000 thinking in some damage or doa, i have now battery connector indicator working, but had this problem:

1) with u7000 soldered this time and also the other time i have no 3.3 volt on 3.3volt coil.
2) if i remove u7000, i have 3.3 volt on coil.

in both case, i have 3.35volt on g3hot.

all voltage seems ok, except the 12.5volt output . on battery fuse, with magsafe only i have 3 volt. when i put battery i have 11.5 volt.

i have 3.89volt on pin3 of u7000.

checked most resistor and all seems ok. changed also the 2 fets q7030, q7035 and still the same. r7010, r7011 all ok.

any other tips would be apprecciated.

at first after solder back u7000, i had green magsafe, even if no 12.5 volt but only 3 volt on battery fuse and also no 3.3 volt on coil. now magsafe light is dep green....

 

[Wuchi]

you will never be a 100% sure... you need to try..... check the gates lines for the fets... the fets itself... and if all checks out, change charge ic and the smc if not solved with the charge ic....
This is the best way to find a solution

So in my post #3148 there is a pic of one mosfet right? And the pin that has 12volts is the grid? And pins that are getting 13volts are source? So shouldn't the drain side have more than 6volts?

 

[macattack600]

K90i 13" 820-2936-A Shorted U7200 need help

Upon comparing a good 100% working board to a dead board I accidently shorted saw a spark on the 2 large capacitors to the right Of U7200 (TPS51125) C7272 and C7273 where I was testing.

When power button hit no boot the IC is Very very hot and will not boot. Do I need to change U7200 or should I be checking the capacitors, resistors going to it. Any insight greatly appreciated.

 

[dellxps15]

Upon comparing a good 100% working board to a dead board I accidently shorted saw a spark on the 2 large capacitors to the right Of U7200 (TPS51125) C7272 and C7273 where I was testing.

When power button hit no boot the IC is Very very hot and will not boot. Do I need to change U7200 or should I be checking the capacitors, resistors going to it. Any insight greatly appreciated.

i would change u7200., but before that u can remove u7200 and check if capacitors arond are shorted.

edit: just playing with another macbook 13 2008 board 820-2327. i have r6905 =PP18V5_DCIN_CONN blown. replaced and blow again. removed u6990 and no more blown, but strange thing is that there is no short on r6905 pins..... bad u6990 ?

 

[macattack600]

Caps different readings

i would change u7200., but before that u can remove u7200 and check if capacitors arond are shorted.

edit: just playing with another macbook 13 2008 board 820-2327. i have r6905 =PP18V5_DCIN_CONN blown. replaced and blow again. removed u6990 and no more blown, but strange thing is that there is no short on r6905 pins..... bad u6990 ?

I removed u7200 from parts board. I tested C7272 ad C7273 on parts board resistance climbs on both but on the shorted board it does'nt climb on the one with the short stays put low reading is that cause its in circuit with the bad qfn?

I don't have a small tip solder iron at the moment is it bad risk to use left over solder still on pads with some flux to reattach U7200?

Maybe I should change the Caps on both side first? but they will short cause short maybe in U7200 i'm just nervous trying to avoid change QFN.

 

[dellxps15]

I removed u7200 from parts board. I tested C7272 ad C7273 on parts board resistance climbs on both but on the shorted board it does'nt climb on the one with the short stays put low reading is that cause its in circuit with the bad qfn?

I don't have a small tip solder iron at the moment is it bad risk to use left over solder still on pads with some flux to reattach U7200?

Maybe I should change the Caps on both side first? but they will short cause short maybe in U7200 i'm just nervous trying to avoid change QFN.

didnt get exactly what u mean..... to better test if caps are ok,ill suggest to remove first u7200 as it get hot. and if u never removed it, it's ok to reuse it's solder to attach a new one. just remove it, put some flux and install the new one. it will get in position automatically even if u little move it.

 

[Wuchi]

What is the correct voltage on pin 16 on u7000 charger bgate when it should open the mosfet near battery?

 

[Wuchi]

I've put a red circle around this green component in the picture. What is it? Is it a capacitor? Measuring it won't give any value and if I measure continuity the signal goes right through an multimeter beeps.

 

[macattack600]

Question about voltage on Q7035 Q7030

A1286 820-2330-a

With Charger no batt
Q7030 10.6V
Q7035 18.7
With both
Q7030 the voltage no reading like blown
Q7035 18.8V
With battery only
Q7030 11.7v
Q7035 11.9v

Q7030 is supposed to be at 12.6 always right? Pin 14 on charger ic gives 4.3v and charges but drains battery 1 indicator light a day.

update---I change Q7030 I have better voltage of 12.1 then I measure at U7070 maybe I short something myself but now I get 4v where 12v should be everwhere and then I plug charger and isl6258a charger ic is very very hot , and now I have dim light on magsafe no charging. It does however sense the charger cause the light indicator while light up at it's charged point nothing else.

 

[tiagobaracho]

I've put a red circle around this green component in the picture. What is it? Is it a capacitor? Measuring it won't give any value and if I measure continuity the signal goes right through an multimeter beeps.

its a capacitor..
Usually if it was not corroded by water damage, if you do not measure shot, it should be fine...

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So in my post #3148 there is a pic of one mosfet right? And the pin that has 12volts is the grid? And pins that are getting 13volts are source? So shouldn't the drain side have more than 6volts?

that 6v goes to 0v when activated... ..
I do use a lot of osciloscope to fix bords... but as i said before, your next step would be change the charger IC and the SMC to se if it fixes.... the only thing before are check on caps and resistor on those ICs arounds..

 

[greekhero]

Macbook Air 2012 A1466 CPU too hot keeps restarting

Hello all,

I have a water damaged Macbook Air 2012 that keep restarting right after turning on. It seems that it might be getting turned off as the CPU is too hot to touch. I have checked all known voltages (per schematic) and they all seem fine. None of the rail seem to be shorting to the ground. just for kicks changed the solder paste as well but still no luck. There are no obvious corrosions to infer that there is one obvious short. Any suggestions as where I should start from?

Heat up normally indicates a short right? Also, it seems that the RAM on the board is also getting rather hot.

Thanks!

 

[Wuchi]

its a capacitor..
Usually if it was not corroded by water damage, if you do not measure shot, it should be fine...



----------



that 6v goes to 0v when activated... ..
I do use a lot of osciloscope to fix bords... but as i said before, your next step would be change the charger IC and the SMC to se if it fixes.... the only thing before are check on caps and resistor on those ICs arounds..

Sorry about my english, but what do you mean by "if you do not measure shot"?

Ok. I thought that something should happen to grid voltage that opens the way for source to be connected with drain. The drain is now connected with the batteryconnector +.

 

[tiagobaracho]

Sorry about my english, but what do you mean by "if you do not measure shot"?

Ok. I thought that something should happen to grid voltage that opens the way for source to be connected with drain. The drain is now connected with the batteryconnector +.

If you do not measure short... ( 0 ohms or close),,, meaning that a capacitor that has close to 0 ohms is a bad cap... in short.. like a bridge or 0 ohms resistor.

 

[macattack600]

Here is some voltages around charger chip. Magsafe on and battery connected.

edit. and for additional info for everybody who wants to help: mid2010 mbp, doesn't charge, detects battery and tells cycles etc. works alone with battery, works with battery and magsafe, doesn't work with magsafe only (except smc bypass mode)

This happens still if you have changed the charging ic?

 

[wesk18]

820-2879-b

Hello All,

I'm trying to fix my friends mac book, the motherboard is a 820-2879-b, it sees the battery and charger but it wont power on i tried jumping the two pins with no luck, i look for any burnt components didn't find any, where should i start checking?