OK I am at a loss at this point then. I'd try the old/original SODIMMs again with the battery removed and using the magsafe only. Maybe the new SODIMM you installed 2 weeks ago died of early failure (not uncommon). Next, I'd also try a known good and charged battery (with the magsafe disconnected), you should again see the G3HOT (3.42v), and the 12v at the fuse. If these are OK, I'd try to power on using Dadiohs method of grounding the pin by the keyboard connector (earlier post), OR try a known good A1278 keyboard assembly.
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SMC Issue on MBP 13 - Hardware Troubleshooting Guide
- Thread starter Dadioh
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OK I am at a loss at this point then. I'd try the old/original SODIMMs again with the battery removed and using the magsafe only. Maybe the new SODIMM you installed 2 weeks ago died of early failure (not uncommon). Next, I'd also try a known good and charged battery (with the magsafe disconnected), you should again see the G3HOT (3.42v), and the 12v at the fuse. If these are OK, I'd try to power on using Dadiohs method of grounding the pin by the keyboard connector (earlier post), OR try a known good A1278 keyboard assembly.
The picture with the pull up resistors was posted on reply #338 page 14 but it was of a MB 2010 so they may be in a different position for the MBP 2011.
Anybody any ideas on a MBP 13" that ac adapter is green or orange if battery needs to charge , G3hot is good but just wont power on either through the power button, G3hot short or keyboard short?
Fan doesn't budge at all - I have measured the keyboard connector senses when the power button is pressed but no reaction and not believing my eyes I even changed the keyboard out! (It's funny how these things drive you in desperation to replace things you logically have already ruled out
).It is strange because everything appears ready to go ... I have tried to reset pram, SMC bypass but nada nothing.
Anyone come across this before?
I just got a 2010 MBP 13'' logic board today that will do exactly what you describe.It charges battery,Magsafe is either green or orange if charging,G3hot is good.It won't power up no way no how.I can get the sleep light to come on if I short G3hot & keyboard at same time.Light just flashes from bright to dim as if it was in sleep mode.Nothing seems to get hot.Very little liquid damage.Any ideasThe picture with the pull up resistors was posted on reply #338 page 14 but it was of a MB 2010 so they may be in a different position for the MBP 2011.
Anybody any ideas on a MBP 13" that ac adapter is green or orange if battery needs to charge , G3hot is good but just wont power on either through the power button, G3hot short or keyboard short?
Fan doesn't budge at all - I have measured the keyboard connector senses when the power button is pressed but no reaction and not believing my eyes I even changed the keyboard out! (It's funny how these things drive you in desperation to replace things you logically have already ruled out
It is strange because everything appears ready to go ... I have tried to reset pram, SMC bypass but nada nothing.
Anyone come across this before?
worked like a charm
thank you!
i also 2009 mbp 13 2.26ghz
it will boot from a charged battery no problem and function 100%
it will not recognize a charger or charge a battery
the magsafe will stay dim
i have already tried swapping magsafes so I know its a board problem
I also checked the dcin fuse which is ok
do you know which compontent controls the charging on the logic board so I can swap it
Glad it worked for you. The MBP problem you had could be due to a bad DCIN board.
Update..
I took it to Apple store after getting nowhere with my attempts
I just got an update from apple store saying it was the top case which was faulty not the logic board .I'm gonna get it repaired by them . so I thought this might help someone with similar symptoms .
thanks for your time guys
I took it to Apple store after getting nowhere with my attempts
I just got an update from apple store saying it was the top case which was faulty not the logic board .I'm gonna get it repaired by them . so I thought this might help someone with similar symptoms .
thanks for your time guys
Thanks for the update. By posting your results no matter how it got done, it will benefit others with similar symptoms.
excellent thread.
I've got a late 2008 unibody 13" macbook (MB466LL/A).
Was working perfectly, and then it was dropped.
Now it only powers on via the SMC bypass but without the battery installed.
With the battery in, the machine doesn't boot. If the machine is on and the battery is put in, the machine instantly powers off. Only the first LED of the battery indicator light blinks with or without the battery in.
The magsafe has a very dim flashing green/orange LED. (though the LED was a dim green before the drop)
Any clues on where to start checking first?
I've got a late 2008 unibody 13" macbook (MB466LL/A).
Was working perfectly, and then it was dropped.
Now it only powers on via the SMC bypass but without the battery installed.
With the battery in, the machine doesn't boot. If the machine is on and the battery is put in, the machine instantly powers off. Only the first LED of the battery indicator light blinks with or without the battery in.
The magsafe has a very dim flashing green/orange LED. (though the LED was a dim green before the drop)
Any clues on where to start checking first?
1. With magsafe off, measure voltage on battery connector pins 1/2/3 vs 7/8/9. You should see a voltage between 10-12 volts, with 12.5v being full charge. If you don't have this, then the battery is bad or in need of a charge. You said the battery test button shows one LED, so I think the battery internally is almost discharged. I suspect you'll measure about 10v or so.
Oops, in a unibody with internal battery pack, the battery test button is on the side of the unibody itself, thus if the battery is unplugged, I fail to see how you can get one LED lit up. The test button sends a signal to the SMC which then "talks" to the battery internal circuit to get voltage level status. With it disconnected, it should not have lit up any LED. Is yours the consumer removable kind?
2. If you see 12v there, then measure the voltage at the fuse near it (white square/rectangular piece. You should see 12v on both side. If no voltage on both ends, then maybe there is a damage to power FET that gates battery power to the system/charging circuit.
Yep. removable battery. The only aluminum macbook.later became the macbook pro.
I can't seem to find that white fuse. I see a couple, but they arent where that pic at the beginning of the thread indicates. I'll take some pics later, cleaning my macro lens right now.
Just wondering if you checked Q5315 or if it would cause it to not power up.Its that tiny sot-963 chip thats the same as q6910(ntud3127cxxg).Its located in the same spot on 2008,2009 & 2010 aluminum Macbooks.It's just above the memory slot to the left.I believe its no good on my 2010 but can't seem to find a replacement yet.ThanksThe picture with the pull up resistors was posted on reply #338 page 14 but it was of a MB 2010 so they may be in a different position for the MBP 2011.
Anybody any ideas on a MBP 13" that ac adapter is green or orange if battery needs to charge , G3hot is good but just wont power on either through the power button, G3hot short or keyboard short?
Fan doesn't budge at all - I have measured the keyboard connector senses when the power button is pressed but no reaction and not believing my eyes I even changed the keyboard out! (It's funny how these things drive you in desperation to replace things you logically have already ruled out
It is strange because everything appears ready to go ... I have tried to reset pram, SMC bypass but nada nothing.
Anyone come across this before?
Thanks - Mine is a 2011 so it is located to the right of the SMC but it appears good.
It is interesting as the SMC appears content as it gives the green ac ok or orange charging battery and the SMC bypass yields no results which seems to confirm that nothing is holding back the SMC yet strangly enough when power button is pressed, or keyboard pin 5 shorted or G3hot shorted (and I dont know how you did multiple all at the same time !) NOTHING happens .. not a flicker on life !
I got more information and apparently, all was working except the notorious dim screen and the owner replaced the blown fuse whithout disconnecting the battery so the board had voltage applied and I guess the soldering iron shorted it out.
Because all the voltages appear correct and SMC is happy I am a little lost as to where to start looking?
Hello.And i'm sorry to bother you.Macbook aluminium.Starting only from battery.No light on adapter,no charging.I take only 0,27 volts on pin 2,4 at magsafe board.Fuses near battery and underside logic board near magsafe board plug give 0 volts.I bought new magsafe board from ebay.Nothing changes.Magsafe adapter gives 6.55v on both 2,4 pins.If i short pin 2,3 or 3,4 adapter raises volts to 16.95.Please help me.I will give any additional information you want.
Oops! I just tested mine again with my new probes & its good.I checked it at least 2 times before I posted the first time & thought for sure it was bad.Strange but true.Sorry if I miss lead you.Cheers
As for doing both at same time..just bare a piece of wire & put one end under a screw or through a hole in mobo.Then with left hand run other end of wire across keyboard connector while holding screw driver on G3hot with right hand.
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You were on the right track though!
I did some digging and the "PBUS VOLTAGE SENSE & FILTER" Q5300 (MBP 2011) another one of those NTUD3169CZ SOT-963 little suckers you mentioned manages the PBUS_G3H state to the SMC. In my case the FET is working but it is reporting "SMC_PBUS_VSENSE" high to the SMC which is preventing initialization as the input "PM_SLP_S3_R_L" is low and should be high.
This leads me to the POWER CONTROL / ENABLE page that has the matrix we talked about earlier in the thread that monitors S0 state (Run) , S3 (sleep) states etc which is interesting as you indicated that yours appeared to be in a sleep state when you managed to power on shorting both keyboard pin 5 and G3HOT.
I think if we can understand this page I think it will lead us to understand this "power good but wont initialize" state we are all getting stuck on.
In my case , I now have a lead with PM_SLP_S3_R_L thanks to your help which is much appreciated so I'll dig some more and report back
Very very interesting. I have a couple of boards that will not power up. I have tried both the G3Hot short as well as keyboard pin 5 with no success. But I had not thought of trying both at the same time. I may give that a shot.
Another test point that I would really like to find is the ALL_SYS_PWRGD line since that is a summation of most of the power supplies on the board. It then gets ANDed with VR_PWRGOOD_DELAY to give a power good signal to the MCP. I figure this would provide a quick way to determine if one of the power rails was bad. So if we can find that AND gate U2850 74LVC1G08GW in SOT353 package (on MBP13 2010) that would help a lot. Free cookie to first one to find it
I waas curious about the relationship between keyboard pin 5 and the power pads on the logic board. It seems they are the same signal other than a 1K resistor between them. So I am puzzled why grounding both simultaneously would have a different effect? See attachments.
Attachments
Hello everyone! I just came across this thread and I must say it has grown to be quite interesting! I have had some success in resurrecting a few boards myself. I just picked up an smd rework station equipped with infared and hot air to perform the delicate surgery needed in repairing these boards. I also picked up a usb 20x magnification video camera. Maybe we can combine our resources to track down and document known symptoms locations and solutions in repairing some of these boards. I have a stack of water damaged boards that I intend on dissecting and experimenting on.
It seemed to me there should be no difference when attempting to power the board from the pad or the keyboard connector. The 1K resistor is just for protection of the SMC chip. Note that all/most SMC signal pins including SMC_ONOFF_L are normally pulled up to logic high (actually to 3.42v from G3HOT by a 10K Ohm resistor). What different behavior are you seeing?
I have not personally seen a difference. I was referring to peislander comment further up in the thread. It sounded like they had seen a difference doing both keyboard and the pads on the logic board.
2010 MBP 13" - no boot, doesn't charge battery
I've gotten some great info from this thread. It's quite a resource. So, here's my current issue: I have a 2010 13'" MBP, spill damaged according to previous owner. They said the spill went into the keyboard, so I've replaced that with a known good one. The battery still has some charge, and when installed will light up 4 leds on the battery indicator board however it won't take any more charge. On the pins for the battery connector I get 3.4v on the sense lines, but nothing on any of the other ones. Does anyone have any advice on where to begin troubleshooting and perhaps what to look for?
I've gotten some great info from this thread. It's quite a resource. So, here's my current issue: I have a 2010 13'" MBP, spill damaged according to previous owner. They said the spill went into the keyboard, so I've replaced that with a known good one. The battery still has some charge, and when installed will light up 4 leds on the battery indicator board however it won't take any more charge. On the pins for the battery connector I get 3.4v on the sense lines, but nothing on any of the other ones. Does anyone have any advice on where to begin troubleshooting and perhaps what to look for?
You will need to focus on the charger circuit. First, do you get a green led on the magsafe charger? If not then one possibility is that the charger circuit is not giving a CHGR_ACOK signal which is a 3.3V signal from the charger to the SMC.
Attachments
Dadioh- there is a green light when the MagSafe is plugged in. I think the first place I need to check is what could be stopping the battery from putting out power to the board and stopping it from taking power from the board to charge. Some things I forgot to mention in the first post are that I have 3.4v at the G3Hot pad that others have used to start their machines by bridging it to the one next to it when the MagSafe is plugged in. The machine is also unresponsive to your SMC bypass mentioned at the beginning of the thread.
I had a similar issue with a 15", which would intermittently charge the battery. Resoldered the SMC chip using an SMD rework station and it worked fine (and still does). Double check that everything is cleaned before you go crazy trying to diagnose the board, be sure to check underneath the BGA ICs. Liquid likes to pool up around the LCD connector, which contains all of the charger enable circuitry.