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SMC Issue on MBP 13 - Hardware Troubleshooting Guide
- Thread starter Dadioh
- Start date
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Helloo,
My sig. other has a 820-2936-A and did a white wine spill (throwing a pillow after my parents in law's dog
). Anyways, I inherited the problem (with the laptop...) To start out with it was dead. After a first clean-up (Isopropropyl alcohol and toothbrush), it booted up and ran off its (low) battery, but would not charge. (Low battery can't test Coconut).
After a second a clean-up, the green diode on an original charger (A1344) will come on, but after a few minutes it will slowly fade out. With the magsafe still active, I get a return voltage of 16.75V(!) on the third pin/adapter sense on the 820-2565-A. Pins 2 and 4 deliver 17.0V. I get 3.45V from the U6900 pin-1. Please note the charring on the 2565 if relevant.
1 Can any deductions be made already there (eg faulty 2565)?
2 If not, I need to dig further. Anyone willing to share the schematics and boardview also (thank you Louis Rossmann) for 820-2936-A? I do have openboardview (thank you Paul Daniels et al).
Before knowing about the high voltage on the third pin, I also tried hooking up the battery to the board and then an aftermarket charger. This resulted in the processor quickly developing high temperatures (and me disconnecting the setup). During the time both were hooked-up, the charger diode did not switch over to amber.
Thanks for any kind of feedback,
T
My sig. other has a 820-2936-A and did a white wine spill (throwing a pillow after my parents in law's dog
). Anyways, I inherited the problem (with the laptop...) To start out with it was dead. After a first clean-up (Isopropropyl alcohol and toothbrush), it booted up and ran off its (low) battery, but would not charge. (Low battery can't test Coconut).After a second a clean-up, the green diode on an original charger (A1344) will come on, but after a few minutes it will slowly fade out. With the magsafe still active, I get a return voltage of 16.75V(!) on the third pin/adapter sense on the 820-2565-A. Pins 2 and 4 deliver 17.0V. I get 3.45V from the U6900 pin-1. Please note the charring on the 2565 if relevant.
1 Can any deductions be made already there (eg faulty 2565)?
2 If not, I need to dig further. Anyone willing to share the schematics and boardview also (thank you Louis Rossmann) for 820-2936-A? I do have openboardview (thank you Paul Daniels et al).
Before knowing about the high voltage on the third pin, I also tried hooking up the battery to the board and then an aftermarket charger. This resulted in the processor quickly developing high temperatures (and me disconnecting the setup). During the time both were hooked-up, the charger diode did not switch over to amber.
Thanks for any kind of feedback,
T
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Helloo,
My sig. other has a 820-2936-A and did a white wine spill (throwing a pillow after my parents in law's dog
After a second a clean-up, the green diode on an original charger (A1344) will come on, but after a few minutes it will slowly fade out. With the magsafe still active, I get a return voltage of 16.75V(!) on the third pin/adapter sense on the 820-2565-A. Pins 2 and 4 deliver 17.0V. I get 3.45V from the U6900 pin-1. Please note the charring on the 2565 if relevant.
1 Can any deductions be made already there (eg faulty 2565)?
2 If not, I need to dig further. Anyone willing to share the schematics and boardview also (thank you Louis Rossmann) for 820-2936-A? I do have openboardview (thank you Paul Daniels et al).
Before knowing about the high voltage on the third pin, I also tried hooking up the battery to the board and then an aftermarket charger. This resulted in the processor quickly developing high temperatures (and me disconnecting the setup). During the time both were hooked-up, the charger diode did not switch over to amber.
Thanks for any kind of feedback,
T
View attachment 804044 View attachment 804045 View attachment 804034 View attachment 804035
Hi,
see attached file ( rename lb_820-2936-a.rar to extract file)
Hah thanks, we'll see about that..!
Right now, I'm just pleased to be able to find the dang components...[doublepost=1542715685][/doublepost]Weird but good! After a fifth Isopropropyl alcohol (and toothbrush) drench yesterday, spending the night and half a day in front of a fan blowing cold air, the logic board is giving me a steady green light on the magsafe on today's second trial run (the first test was no different than in my earlier post). The adapter sense Voltage has now dropped from previous 13.5-16.75V to now 4.59V. Perhaps this is only temporary, but watching the green diode is a bliss!
When I first hooked up the magsafe this second time no green nor amber lit up, I left it connected getting ready to test the onewire circuit, thanks to fabry79. A number of minutes after starting to test the circuit, the green diode suddenly lit up, the cpu was hot at that point, but cooled down, and now still I'm looking at stable green?! I don't get it, but am happy as a fiddle and am unwilling to disconnect...
Ok, back to black... I disconnected the magsafe after having green for an hour. When I hooked it back up, no diode.
U6900
Pin 1: 3.45V
Pin 4 (INT): 3.45V
Pin 5 (EXT): unstable, jumping around 9V one time and 16.5V the next
R6900
67kOhm (supposed to be 100kOhm) when measuring between 1 and 2
Pin 1 same behavior and Voltage as Pin 5 on U6900
I wonder what component supplies the varying Voltage to Pin 5..?
EDIT1
Search and you shall (hopefully) find, Louis Rossmann answers my question in "How to tell a bad charging port from a bad logic board on a Macbook"
, thank you Louis!
Pin 5 on U6900 is being fed by the DC-In. Mine is leaking the higher Voltage onto the 1-wire, and thus the U6900 does not allow charging the board (and battery). I'll try replacing it..!
EDIT2
I tested a known good DC-In on the logic board above with the same magsafe, and Eureka it works! Unfortunately I didn't test if the fan etc started, so that'll be a suspenseful wait until I have the new DC-In connected.
EDIT3
The new DC-In finally arrived and was hooked up today, and good news:
1 Green diode when connecting the magsafe
2 Fan starting
3 With battery connected the magsafe goes from green to amber
Next step will be to put everything back together and see if all is in order...!
U6900
Pin 1: 3.45V
Pin 4 (INT): 3.45V
Pin 5 (EXT): unstable, jumping around 9V one time and 16.5V the next
R6900
67kOhm (supposed to be 100kOhm) when measuring between 1 and 2
Pin 1 same behavior and Voltage as Pin 5 on U6900
I wonder what component supplies the varying Voltage to Pin 5..?
EDIT1
Search and you shall (hopefully) find, Louis Rossmann answers my question in "How to tell a bad charging port from a bad logic board on a Macbook"
Pin 5 on U6900 is being fed by the DC-In. Mine is leaking the higher Voltage onto the 1-wire, and thus the U6900 does not allow charging the board (and battery). I'll try replacing it..!
EDIT2
I tested a known good DC-In on the logic board above with the same magsafe, and Eureka it works! Unfortunately I didn't test if the fan etc started, so that'll be a suspenseful wait until I have the new DC-In connected.
EDIT3
The new DC-In finally arrived and was hooked up today, and good news:
1 Green diode when connecting the magsafe
2 Fan starting
3 With battery connected the magsafe goes from green to amber
Next step will be to put everything back together and see if all is in order...!
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Hallo,
i have an Mac Book Pro 13" Mid 2012 i5.
The Problem that i have is:
Mag save is OK. Led is Gren/Orange when Load Battery.
Battary is OK and New.
When i press the Power Button the Mac do nothing!
When i warm up the Logig Board with a Hair Phön, for a few seconds. (near the DC Board on the Logig Board) and i put Power on. The mac is Running without Problems. He is running so Long, till i turnd off and wait 15-30 minutes. after the Mac is Cold he is Dad. when i press the Powerbutton between 10-15 min the mac booted and will runnung ok.
SMC Reset is doing. after that i press the Power button and the Fan is Running, but nothing else. Only the fan.
I Think it is a Temparatur Problem??
Who can help me?
i have an Mac Book Pro 13" Mid 2012 i5.
The Problem that i have is:
Mag save is OK. Led is Gren/Orange when Load Battery.
Battary is OK and New.
When i press the Power Button the Mac do nothing!
When i warm up the Logig Board with a Hair Phön, for a few seconds. (near the DC Board on the Logig Board) and i put Power on. The mac is Running without Problems. He is running so Long, till i turnd off and wait 15-30 minutes. after the Mac is Cold he is Dad. when i press the Powerbutton between 10-15 min the mac booted and will runnung ok.
SMC Reset is doing. after that i press the Power button and the Fan is Running, but nothing else. Only the fan.
I Think it is a Temparatur Problem??
Who can help me?
(...)
I was thinking at some point I should grab a lot of the generic info and put it all in the first post to make it easier for people to learn the basics without needing to read the whole thread. Finding the time is the problem
(...)
Hello Dadioh,
yes, I think so too, since I've read every post here in the last 3 days - and it's only page 17 of 145!
Somehow I thought at one point:
There are so many different problems:
• No function on the MagSafe adapter (MagSafe LED off)
• No charging function of the battery (MagSafe = green)
• MagSafe reacts normally (green), jumps to amber when charging the battery. But the MB(P/A) does not start anyway
• MB(P/A) only starts with the battery present
• MB(P/A) only starts with DCin
• MB(P/A) starts with DCin only when the battery is not connected
• MB(P/A) starts with DCin when a battery is connected
...
And every time the search starts again from the beginning, with a different starting point an for different boards...
Now I think it would be cool to create a flowchart that discusses the individual problem areas and links them to the corresponding posting here in the thread (if that were possible, in the confusion in this thread).
But all the work you, cmdrdata, peislander and others have done is unfortunately not systematic enough on 145 pages of a thread ... Or I'm not able to filter them well ...
In any case, this thread is legendary and even after almost 10 years, gold value!
Thank you very much at this point.
I'll try to add my findings and questions as well, if I've read through the thread - do not dare to describe my problem, because there are still hundreds of exactly such requests until the end of the thread and somewhere the answer is in the 145 Pages of the thread stuck ;-) Gotta find them...
Best Regards
Georg
Facing same issue... found Wife's 13" MBP one night with the case appearing to be swollen, opened screen and trackpad was bulged out. Immediately thought battery had died and swelled. Sure enough that was the case. However after removing battery and plugging in, it worked fine. Ordered a new battery, put it in and it seemed to be working fine and charging. Few days go by....
Now the laptop won't start, no battery indicator, nor green light on magsafe. Searched around, found some info on "one-wire circuit" and started checking the logic board.
I don't see any damage, maybe a few spots that have a reddish/brown discolored on some of the gold pads. Maybe light corrosion from possible gas leaked from damaged battery.
Logic board is a 820-2936B and I'm getting no power on: PPBUS_G3H or PP3V42_G3H. I'll double check U6990, but I had voltages of 16.3 input, 14.5 input with resistor and 3.8 V on FB IIRC.
Now the laptop won't start, no battery indicator, nor green light on magsafe. Searched around, found some info on "one-wire circuit" and started checking the logic board.
I don't see any damage, maybe a few spots that have a reddish/brown discolored on some of the gold pads. Maybe light corrosion from possible gas leaked from damaged battery.
Logic board is a 820-2936B and I'm getting no power on: PPBUS_G3H or PP3V42_G3H. I'll double check U6990, but I had voltages of 16.3 input, 14.5 input with resistor and 3.8 V on FB IIRC.
Dear All,
i'm a Macbook a1278 - mptherboard 820-2978 b - that have following problems :
- magsafe connected,green light ( without battery ) mac doesn't start.
- magsafe connected,green light ( with battery ) mac start but no orange light ( no battery charge)
Seems that no water damages.
now using following Dadioh info,
I've below situation:
Pin 1 - 0V - CHGR_AGATE --> 0V
Pin 2 - 16V - CHGR_DCIN -->16,36 V
Pin 3 - 4V - ACIN - Resistor divider 30K/9.31K (DCIN / 4) -->3,9V
Pin 14 - 3.3V - ACOK - Signal to SMC that charger is happy.-->3.27 V
Pin 17/18 - 12.5V - CSOP/CSON - Measured across sense resistor to/from battery -->11,01V
Pin 19/20 - 5V - VDD/VDDP - internally generated 5V supply -->5,8 V
Pin 23 - 12.5V - CHGR_PHASE - Output of charger -->11,02 V
Pin 27/28 - 16V - CSIP/CSIN - Current Feedback from sense resistor feeding FETS -->16,07V
Do you any suggestion?
Tnx for help
Hi, did you find any solution?
[automerge]1582921229[/automerge]
Guys, I won a macbook pro 2011, but he has some problems, he is not able to charge the battery, when I connect the MagSafe, only lights the green led and if the battery is zero it does not turn on, but if it has a charge (100 %) it works without any problem, I bought a DC-in card and I'm waiting to arrive ... has anyone experienced this problem? And can you help me?
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A1226 Santa Rosa 15" MacBook Pro. Served me ok for six years 2007-2013. 85W brick, new Magsafe lead gives me a green light. Apple battery is dead and doesn't charge from green light/off mode or no green light/SMC_debug mode.
Fitted a used eBay LIO bd as I'd massacred the Magsafe receptacle on the OEM bd, no start-up, then found R6907 (47 ohms) on eBay LIO bd to have gone high, around 200 so found a 51 ohm SMD from a junk board and it now starts fine in SMC debug/bypass mode. Obviously the usual maxed-out fans, no keyboard backlight.
No liquid damage, no obvious corrosion or burnt components. It has suffered from severe fluff build-up, but I had always run it on a fan-plinth.
It's had the GPU repair done successfully under recall, and I successfully changed the trackpad flatstrip cable.
It boots from an Expresscard SSD and runs fine in el Capitan, or Snow Leopard on the HD. No lag at all. I installed the ASD tests in a separate HD partition and ran a few tests, but they don't have sensor tests in this version, ASD-3S116.
USB reads a stick ok and FW has power on it. There's 3V42 always, and I presume 3V3 and 5V when hotwired, as all functions seem normal for SMC debug mode.
Belled heatsink thermal sensor in diode mode on spare and on sensor fitted and both give 0.6v.
I've been googling around and have yet to find detailed tech info on SMC_debug mode or on the sensor/input requirements for the SMC. I've got another cheapo LIO bd coming, but after that I'm not throwing any more money at it. I'll be making a 555 PWM fan control and turn it into a Frankentosh. But I've a feeling it's a hairline crack or a dry joint away from fixing.
Any ideas from this unbelievable Megathread?
Cheers from House-Arrest Spain.
Fitted a used eBay LIO bd as I'd massacred the Magsafe receptacle on the OEM bd, no start-up, then found R6907 (47 ohms) on eBay LIO bd to have gone high, around 200 so found a 51 ohm SMD from a junk board and it now starts fine in SMC debug/bypass mode. Obviously the usual maxed-out fans, no keyboard backlight.
No liquid damage, no obvious corrosion or burnt components. It has suffered from severe fluff build-up, but I had always run it on a fan-plinth.
It's had the GPU repair done successfully under recall, and I successfully changed the trackpad flatstrip cable.
It boots from an Expresscard SSD and runs fine in el Capitan, or Snow Leopard on the HD. No lag at all. I installed the ASD tests in a separate HD partition and ran a few tests, but they don't have sensor tests in this version, ASD-3S116.
USB reads a stick ok and FW has power on it. There's 3V42 always, and I presume 3V3 and 5V when hotwired, as all functions seem normal for SMC debug mode.
Belled heatsink thermal sensor in diode mode on spare and on sensor fitted and both give 0.6v.
I've been googling around and have yet to find detailed tech info on SMC_debug mode or on the sensor/input requirements for the SMC. I've got another cheapo LIO bd coming, but after that I'm not throwing any more money at it. I'll be making a 555 PWM fan control and turn it into a Frankentosh. But I've a feeling it's a hairline crack or a dry joint away from fixing.
Any ideas from this unbelievable Megathread?
Cheers from House-Arrest Spain.
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Hey at all,
I got a MBP 2012 with a 820-3115-B Board.
It did not start and had a very dim light on the charger. I figured out it has a short on PP3V42_G3H. Replaced C6405 which was shorted but that didn't help.
Injected voltage into the board and narrowed down the short to the SMC.
Desoldered the SMC and replaced it with a SMC form a donor board (it was my first time recalling any BGA).
Now I get a green light on the charger and as soon as I plug in the charger, with the battery disconnected, the board starts and boots just fine.
Two problem are remaining:
1. The board does neither detect the battery nor does the charger give me an amber light.
2. I can not start the Macbook with the power button once I shut it down like normal.
- I already checked WS_KBD_ONOFF_L going low and high again. So I assume the power button is working.
- I only get 12.3V on PPBUS_G3H which makes me believe the SMC is not running and thus also the battery not charging.
- Also SMBUS_CHGR__SDA is up at 3.49V
- Macbook does not start in SMC bypass mode
I'm searching the internet for about 5 days now but didn't come up with a proper solution.
What do you guys think could be the problem. I only had one SMC on a donor board so I can't be 100% sure that it was fine or that I messed up the SMC while reballing it.
Thanks in advance, cheers!
I got a MBP 2012 with a 820-3115-B Board.
It did not start and had a very dim light on the charger. I figured out it has a short on PP3V42_G3H. Replaced C6405 which was shorted but that didn't help.
Injected voltage into the board and narrowed down the short to the SMC.
Desoldered the SMC and replaced it with a SMC form a donor board (it was my first time recalling any BGA).
Now I get a green light on the charger and as soon as I plug in the charger, with the battery disconnected, the board starts and boots just fine.
Two problem are remaining:
1. The board does neither detect the battery nor does the charger give me an amber light.
2. I can not start the Macbook with the power button once I shut it down like normal.
- I already checked WS_KBD_ONOFF_L going low and high again. So I assume the power button is working.
- I only get 12.3V on PPBUS_G3H which makes me believe the SMC is not running and thus also the battery not charging.
- Also SMBUS_CHGR__SDA is up at 3.49V
- Macbook does not start in SMC bypass mode
I'm searching the internet for about 5 days now but didn't come up with a proper solution.
What do you guys think could be the problem. I only had one SMC on a donor board so I can't be 100% sure that it was fine or that I messed up the SMC while reballing it.
Thanks in advance, cheers!
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Just a quickie---looks like you understand the circuit better than I do, this guy Louis Rossman on YouTube is good https://www.youtube.com/user/rossmanngroup. He's got a vid on the 820-3115 on
I'm the guy in the post above from 10 months ago! No replies ;-( My MBP still boots ok in bypass mode, after I tried a few things then gave up. Good luck!
I basically have the same issue. Except in my experience if I leave it off for a couple of days and plug in the MagSafe it does charge but it seems each time I go through that cycle it does not charge as well as it should or anywhere near 100%.
2nd to last time it got up to 87% and this last instance earlier today it only got up to 37%, though I turned it on after a couple of hours of it not looking like it was going to charge any further (using the battery charge indicator to tell).
If/when I do get it to 100% it lasts and works as normal but it does slowly lose charge, roughly 1% a week. Once it drops to a certain percentage, the drop rate accelerates to 1% every 4 minutes.
Early 2013 13" MBP, A1425. Upgraded SSD, ran fine for a few weeks. Now DEAD; no start-up action at all.
MagSafe LED starts green, goes to amber immediately
Different charger--same result
Tried SMC reset many times--still DEAD.
Testing 4 gold contacts on battery connector
I get ~3.25VDC each side, ~6.41VDC total. Which seems like not enough given that replacement should have ~11.4VDC.
I've looked and search a lot but don't find any answer:
Isn't there some way to test the battery by itself? Is the only way to tell if its' the battery (unless of course it's swollen or something) to buy a new one and see if that fixes the problem? No, sorry, no reports from coconut battery or similar tool.
How can I tell if the battery is just worn out (original battery from 2013) OR if it's the DC in board, or something else?
Eeeeeeeek!
Thanks for any quick assistance.
MagSafe LED starts green, goes to amber immediately
Different charger--same result
Tried SMC reset many times--still DEAD.
Testing 4 gold contacts on battery connector
I get ~3.25VDC each side, ~6.41VDC total. Which seems like not enough given that replacement should have ~11.4VDC.
I've looked and search a lot but don't find any answer:
Isn't there some way to test the battery by itself? Is the only way to tell if its' the battery (unless of course it's swollen or something) to buy a new one and see if that fixes the problem? No, sorry, no reports from coconut battery or similar tool.
How can I tell if the battery is just worn out (original battery from 2013) OR if it's the DC in board, or something else?
Eeeeeeeek!
Thanks for any quick assistance.
I looked at his stuff but didn't find anything specifically related to testing the battery: lots of board diagrams, microsoldering and such.
Thanks!
Thanks!
I wonder if it would be worthwhile just rigging up a makeshift lithum battery pack from, say, 18650 cells, and wiring that it instead? Is it feasable to desolder the existing battery? Considering the age ( I'm happily typing from a late-2013 retina 13") I'd say it's worth saving. iFixit has a battery replacement procedure https://www.ifixit.com/Guide/MacBook+Pro+13-Inch+Retina+Display+Late+2012+Battery+Replacement/13076 but I suppose that's not relevant yet. I guess 4 cells in series would be right?
EDIT this is early 2013 the above was what Google gave me with the A-number, but I think the batteries are the same
MacBook Pro 13" Retina Display Early 2013 Battery Replacement
Use this guide to safely remove the glued-in battery from your MacBook Pro with the help of an iFixit battery replacement kit. The adhesive remover...
www.ifixit.com
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Okie Magic works again!
I took it apart and checked the DC-in and logic boards for corrosion, burnt parts and such. Nothing.
Cleaned VERY thoroughly around the MagSafe connector on the computer. Also scrubbed the pins on the charger side of the MagSafe and ran some alcohol through the spring-loaded pins. One of the pins seemed maybe slightly sticky?
During reassembly I saw a slightly oily film near the AirPort card (separate from the logic board). Took off the AirPort card and there was some similar fluid under that on the non-absorbent foam pad on the underside of the card. Cleaned that all up.
Got it all back together, fired it up and it worked just fine. I have NO idea what I might have fixed or not fixed. System profile software says battery isn't even to 1,000 cycles yet and is in good condition. Problem solved, no idea exactly why, but can't argue with success. Better to be lucky than good.
Thanks all for your help and for being on this forum to help us less talented folks.
I took it apart and checked the DC-in and logic boards for corrosion, burnt parts and such. Nothing.
Cleaned VERY thoroughly around the MagSafe connector on the computer. Also scrubbed the pins on the charger side of the MagSafe and ran some alcohol through the spring-loaded pins. One of the pins seemed maybe slightly sticky?
During reassembly I saw a slightly oily film near the AirPort card (separate from the logic board). Took off the AirPort card and there was some similar fluid under that on the non-absorbent foam pad on the underside of the card. Cleaned that all up.
Got it all back together, fired it up and it worked just fine. I have NO idea what I might have fixed or not fixed. System profile software says battery isn't even to 1,000 cycles yet and is in good condition. Problem solved, no idea exactly why, but can't argue with success. Better to be lucky than good.
Thanks all for your help and for being on this forum to help us less talented folks.
That's good. FWIW I've had lots of problems with MagSafe connectors. Apart from attracting ferro material, they can develop the vicious circle of overheating/oxidising/high resistance/ resulting in pins sticking. I use a cropped-down toothbrush/alcohol on them, and once tried a heavy duty Wahl electric haircutter as a vibration source to free a stuck pin. I'm on my original MagSafe receptacle on the late 2013 13" rmbp but I had to change the plug on the charger lead once to prevent degeneration of the rceptacle. My battery is still ok-ish, it'll drop from 100 to 50 after three hours after having had a life on mostly being on the charger. (Cycle count 422. Condition: Service Battery)