Hi vito1202,
That chip looks badly burnt, it will need replacing before you go any further. It certainly has been hot so it could be the cause of the board shutting down.
Regards,
Chigwelldave.
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SMC Issue on MBP 13 - Hardware Troubleshooting Guide
- Thread starter Dadioh
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Hi vito1202,
That chip looks badly burnt, it will need replacing before you go any further. It certainly has been hot so it could be the cause of the board shutting down.
Regards,
Chigwelldave.
A1278 macbook pro 13 mid2010 820-2879-B
Hi Chigwelldave.
yes I have 16.5v on fuseF6905 but only 000.2v on R7020 and G3 hot is 001.3v so do you think that U7000 is bad or R7020 not passing to U7000 thanks for your help . vic44.
Hi Chigwelldave.
yes I have 16.5v on fuseF6905 but only 000.2v on R7020 and G3 hot is 001.3v so do you think that U7000 is bad or R7020 not passing to U7000 thanks for your help . vic44.
Hi vic44,
If you have lost your g3Hot then not much will work. Check you have battery or mag safe volts (11-18v) both sides of R6905. If OK, see if you have 3.2-3.4v on L6995. U7000 will not function (AFAIK) without G3Hot and U7000 controls Q7080 and Q7085 which have to conduct before R7020 will receive volts.
Regards,
Chigwelldave.
If you have lost your g3Hot then not much will work. Check you have battery or mag safe volts (11-18v) both sides of R6905. If OK, see if you have 3.2-3.4v on L6995. U7000 will not function (AFAIK) without G3Hot and U7000 controls Q7080 and Q7085 which have to conduct before R7020 will receive volts.
Regards,
Chigwelldave.
A1278 macbook pro 13 mid2010 820-2879-B
Hi chigwelldave. sorry I just found R6905 it has 0.250v on both sides. and on L6995 I've only got 1.440v on pin 1 and 1.490v on pin 2 with Magsafe connected.
thanks vic44.
Hi chigwelldave. sorry I just found R6905 it has 0.250v on both sides. and on L6995 I've only got 1.440v on pin 1 and 1.490v on pin 2 with Magsafe connected.
thanks vic44.
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A1278 macbook pro 13 mid2010 820-2879-B
Hi chigwelldave.
no just get 1.44v with the battery connected?
Hi chigwelldave.
no just get 1.44v with the battery connected?
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A1278 macbook pro 13 mid2010 820-2879-B
Hi chigwelldave.
just been looking though the thred and was wondering about the dcin board I checked the pins 1to 5 and im getting
pin 1 0v
pin2 16.2v
pin3 0v
pin4 16.2v
pin5 0v
on old dcin board and new dcin board in the thread it says
pin1 0v
pin2 4.7v
pin3 0v
pin4 4.7v
pin5 0v do you think mine are bad could it be overvoltage on input
dcin board. thanks for looking vic44.
Hi chigwelldave.
just been looking though the thred and was wondering about the dcin board I checked the pins 1to 5 and im getting
pin 1 0v
pin2 16.2v
pin3 0v
pin4 16.2v
pin5 0v
on old dcin board and new dcin board in the thread it says
pin1 0v
pin2 4.7v
pin3 0v
pin4 4.7v
pin5 0v do you think mine are bad could it be overvoltage on input
dcin board. thanks for looking vic44.
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Hi vic44,
The supply for the G3Hot comes from the mag safe or the battery. For the mag safe you should have 16-18v on Q7080 pin5, going through to pins 1,2 & 3. From the battery, it goes through Q7055, R7050, L7030, Q7030, R7020 and Q7085. You could check all these points and see where you lose it. Others on this thread have said the mag safe shuts down after a few seconds if it does not detect a load, so you may need to measure quickly after plugging it in. The battery voltage should be there all the time until the battery is very low and shuts off. Your mag safe voltages are what I would expect.
Regards,
Chigwelldave
The supply for the G3Hot comes from the mag safe or the battery. For the mag safe you should have 16-18v on Q7080 pin5, going through to pins 1,2 & 3. From the battery, it goes through Q7055, R7050, L7030, Q7030, R7020 and Q7085. You could check all these points and see where you lose it. Others on this thread have said the mag safe shuts down after a few seconds if it does not detect a load, so you may need to measure quickly after plugging it in. The battery voltage should be there all the time until the battery is very low and shuts off. Your mag safe voltages are what I would expect.
Regards,
Chigwelldave
A1278 macbook pro 13 mid2010 820-2879-B
Hi Chigwelldave
this is what ive got
with magsafe only
Q7080 pin5 16.67v
pin1 16.07v
pin2 16.08v
pin3 16.08v
then battery only
Q7055 pin5 11.87v
pin1 11.87v
pin2 11.87v
pin3 11.87v
R7050 11.87v both sides
L7030 pin1 11.87v
pin2 11.87v
Q7030 pin5 11.76v
pin1 11.86v
pin2 11.86v
pin3 11.86v
R7020 11.21v both sides
Q7085 pin5 11.60v
pin1 10.62v
pin2 10.62v
pin3 10.62v
thanks again for helping vic44.
Hi Chigwelldave
this is what ive got
with magsafe only
Q7080 pin5 16.67v
pin1 16.07v
pin2 16.08v
pin3 16.08v
then battery only
Q7055 pin5 11.87v
pin1 11.87v
pin2 11.87v
pin3 11.87v
R7050 11.87v both sides
L7030 pin1 11.87v
pin2 11.87v
Q7030 pin5 11.76v
pin1 11.86v
pin2 11.86v
pin3 11.86v
R7020 11.21v both sides
Q7085 pin5 11.60v
pin1 10.62v
pin2 10.62v
pin3 10.62v
thanks again for helping vic44.
A1278 macbook pro 13 mid2010 820-2879-B
Hi Chigwelldave.
I've just been checking round the board and found
that I now have 16.00v on R6905 both sides yesterday I had only 0.250v so I rechecked L6995 now I've got on pin1 1.55v
and pin2 1.48v still with just magsafe.
Hi Chigwelldave.
I've just been checking round the board and found
that I now have 16.00v on R6905 both sides yesterday I had only 0.250v so I rechecked L6995 now I've got on pin1 1.55v
and pin2 1.48v still with just magsafe.
hi, i've had the same problem like you. che u7000 chip coem from china some days ago, but have first to replace 2 0402 capacitors before solder u7000 back in place. mine was not visible damaged, but get very hot and pc didnt start even with keyboard bypass. hope to fix it after replacing the u7000.
Chigwelldave.
Do you happen to know the board location of the TPS51125 on the 820-2915-B board ?
Page 3 of the K91F schematics appear to reference it as U7201 on the page 3 Power System Architecture and later on page 65 references U7201 as a TPS51980.
Thanks.
Do you happen to know the board location of the TPS51125 on the 820-2915-B board ?
Page 3 of the K91F schematics appear to reference it as U7201 on the page 3 Power System Architecture and later on page 65 references U7201 as a TPS51980.
Thanks.
Hi vic44,
Sound like your G3Hot has died then. If you have access to a bench power supply you can supply an external 3.4v to G3Hot to allow you to troubleshoot further. I did this on a board to see if it was good in other respects (no point spending time/money to fix a fault when it's not going to give you a good board). Just set the current limit to 300mA in case there's a fault on the line. If you want to replace the LT3470A, RS Components stock them for $6.50.
Regards,
Chigwelldave
----------
I only have a 820-2915-A board to reference but, if it's similar, the chip is a TPS51980 and is located just below the centre of the right fan, same side as the keyboard connector.
Regards,
Chigwelldave.
Sound like your G3Hot has died then. If you have access to a bench power supply you can supply an external 3.4v to G3Hot to allow you to troubleshoot further. I did this on a board to see if it was good in other respects (no point spending time/money to fix a fault when it's not going to give you a good board). Just set the current limit to 300mA in case there's a fault on the line. If you want to replace the LT3470A, RS Components stock them for $6.50.
Regards,
Chigwelldave
----------
I only have a 820-2915-A board to reference but, if it's similar, the chip is a TPS51980 and is located just below the centre of the right fan, same side as the keyboard connector.
Regards,
Chigwelldave.
Chigwelldave.
Thanks, apparently a TPS51125 is not used on the 820-2915 board altho it is on the K91F schematics so I am not clear on why.
Thanks, apparently a TPS51125 is not used on the 820-2915 board altho it is on the K91F schematics so I am not clear on why.
I think the people doing the schematics use copy and paste a lot, especially the block diagrams. I have found the individual pages quite accurate.
Hi.
My Late 2011 15" MacBook Pro have had a charging issue.It was caused by U7000 ISL6259 - short on pins 10 (SMBUS_SMC_BSA_SDA) and 11 (SMBUS_SMC_BSA_SCL) After replacing U7000 machine will startup only with the magsafe plugged in (it actually powers on itself). Battery is not being charged.
I know for sure it's a 100% working battery (tested with another mac) and It has only 6 charge cycles.
I installed a fresh copy of OS X 10.9 but my battery icon is crossed out.I have been reading previous posts and I found this:
(..)The I2L is a bus, with the SMC being the bus master and one or more devices connected to this bus as the bus slave. This line should normally be pulled up to 3.3v by pull-up resistors connected to G3HOT. The devices driving these lines toggle the lines to ground for short period of time, thus creating pulse Only one device can drive these lines, one at time signals. The pulses on the data line (SDA) are coded so that it sends an address code and then data code. They are also accompanied by a clocking signal on the SCL line.
Now,on U7000 ISL6259 I have:
Pin 14 - 3.28V
Pin 10 - 3.46V - stable
Pin 11 - 3.46V - stable
But I'm not getting that pulse signal at all.
So, do you think that SMC was also somehow affected by that short, and now is not communicating with the battery ?
And here is what the Apple Service Diagnostics says:
[11/28/13 16:30:17]Voltage (VP0R) -- PBus (test #1) - Sensor Reads Within Operating Range (Voltage) - Check to ensure that sensor reads within operating range. \cf3 [16:30:17]ERROR -- 3 [Sensor reading below low point] -- TEST FAILED
BTW. With the magsafe plugged it, what voltage should I have on U7000 pin 21 (CHGR_LGATE) ? Mine is 0V.
My Late 2011 15" MacBook Pro have had a charging issue.It was caused by U7000 ISL6259 - short on pins 10 (SMBUS_SMC_BSA_SDA) and 11 (SMBUS_SMC_BSA_SCL) After replacing U7000 machine will startup only with the magsafe plugged in (it actually powers on itself). Battery is not being charged.
I know for sure it's a 100% working battery (tested with another mac) and It has only 6 charge cycles.
I installed a fresh copy of OS X 10.9 but my battery icon is crossed out.I have been reading previous posts and I found this:
(..)The I2L is a bus, with the SMC being the bus master and one or more devices connected to this bus as the bus slave. This line should normally be pulled up to 3.3v by pull-up resistors connected to G3HOT. The devices driving these lines toggle the lines to ground for short period of time, thus creating pulse Only one device can drive these lines, one at time signals. The pulses on the data line (SDA) are coded so that it sends an address code and then data code. They are also accompanied by a clocking signal on the SCL line.
Now,on U7000 ISL6259 I have:
Pin 14 - 3.28V
Pin 10 - 3.46V - stable
Pin 11 - 3.46V - stable
But I'm not getting that pulse signal at all.
So, do you think that SMC was also somehow affected by that short, and now is not communicating with the battery ?
And here is what the Apple Service Diagnostics says:
[11/28/13 16:30:17]Voltage (VP0R) -- PBus (test #1) - Sensor Reads Within Operating Range (Voltage) - Check to ensure that sensor reads within operating range. \cf3 [16:30:17]ERROR -- 3 [Sensor reading below low point] -- TEST FAILED
BTW. With the magsafe plugged it, what voltage should I have on U7000 pin 21 (CHGR_LGATE) ? Mine is 0V.
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Hello, I have the same board with the same issues, now I troubleshooting the board to localize the fault, but I think the problem is on u4900
Hi.
What voltages are you getting on your U7000? Mine are here:
https://dl.dropboxusercontent.com/u/138757/U7000 15inch.PNG
And here is a what we should be getting on pin 4 and 6 of U7000.Taken from my working A1278:
https://dl.dropboxusercontent.com/u/138757/i2c.gif
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Hi all,
sorry for my english...
I bought a used A1278 2.66Mhz 2010 ,but after 40 days (30 days warranty) does not work anymore '.
All fuse ok
No LEDs light up on magsafe. (there are 16.8V on the fuse F6905 and 12.5 V on battery Fuse F7000 )
Reset .G3hot (short 2 pad near Keyboard connector) on brd (controlled voltage 1.7V)
Do not turn on the fan.
Can you help me?
I need to know where are 'diode D6905, u6990, etc. but I dont have the device layout ( for the cpu side I have landrex file)
sorry for my english...
I bought a used A1278 2.66Mhz 2010 ,but after 40 days (30 days warranty) does not work anymore '.
All fuse ok
No LEDs light up on magsafe. (there are 16.8V on the fuse F6905 and 12.5 V on battery Fuse F7000 )
Reset .G3hot (short 2 pad near Keyboard connector) on brd (controlled voltage 1.7V)
Do not turn on the fan.
Can you help me?
I need to know where are 'diode D6905, u6990, etc. but I dont have the device layout ( for the cpu side I have landrex file)
I make test in the board, I put the multimeter in ohms and check pin 11 and 10 in u7000, pin11 to ground=3,3k and pin10 to ground=3,3k. In a good board the value of resistance are 290k more or less, I think that 2 lines are short to ground, when I remove U7000 and check again, and the result are the same, I remove R5280 and R5281, and the short disappear, I think PP3V42_G3H shorting to ground or internal short through U4900, is possible??
When I press the button to make test from battery, no light see any thing and when the computer it´s on, the OS says "NO BATTERY"
The rest of the functions of macbook work correctly
I check pin 4 and 6, the value is 3,46v in both pins
thank you for help me
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hi guys,
Please help me analysis, your advise/instructions will be very appreciated.
basic information:
-MacBook Pro 13(Mid, 2012) MD101ZP/A
-i5 2.5G CPU/4GB Memory(2 x2G)/500GB HDD/Super Drive
recently, my mbp always auto shut down, all happened in sleeping mode(i close the LCD cover let the system go to sleep). then the unit can not boot up.
Below is the detail symptoms and my try efforts:
1, SIL(sleep indicator light) no response while i press the little button on the left side.
2, plug in A/C adapter, still can not boot, and the adapter charging indicator light no response(only very weak green/orange light blinking).
3, sometimes, i dis-assembly the bottom case. then unplug the battery connector from the motherboard, a few seconds re-plug it to motherboard...the unit maybe turn on, sometime failed.
Please help me analysis, your advise/instructions will be very appreciated.
basic information:
-MacBook Pro 13(Mid, 2012) MD101ZP/A
-i5 2.5G CPU/4GB Memory(2 x2G)/500GB HDD/Super Drive
recently, my mbp always auto shut down, all happened in sleeping mode(i close the LCD cover let the system go to sleep). then the unit can not boot up.
Below is the detail symptoms and my try efforts:
1, SIL(sleep indicator light) no response while i press the little button on the left side.
2, plug in A/C adapter, still can not boot, and the adapter charging indicator light no response(only very weak green/orange light blinking).
3, sometimes, i dis-assembly the bottom case. then unplug the battery connector from the motherboard, a few seconds re-plug it to motherboard...the unit maybe turn on, sometime failed.
Finaly I change U4900 and now the system detect the battery and charge the battery, thank for all,
MBP 13 A1278 big problem
Hi to all! Sorry for my bad English.
After one month of reading all the post in this thread, i was able to fix a problem on my MBP A1278.
The problem was MBP turn on, but no charge.(Magsafe light was dim green)
The cause was no PP3V42_G3H on U6901, i retablished this and nothing happen, so after measure U6901 was not make his job; after replacement no light on the magsafe so I changed then R6929 and U6900.
And then all was ok.
The MBP has working 2 days.
And now the mac won't turn on after a sleeping mode. Have trying the smc bypass; keyboard bypass; g3hot bypass, nothing.
It's a K6 LB, I follow the power sequence and I don't have VIN in U7600 it stay on the Drain of Q7620 (12,46V) and don't have VIN in U7300 voltage stay on the Drain of Q9806 (12,46V). I have a doubt on the U7840 all the voltages seems correct but i have nothing for P3V3S5_EN_L.
It gives more idea in two brains that in one, thank you for your help.
Hi to all! Sorry for my bad English.
After one month of reading all the post in this thread, i was able to fix a problem on my MBP A1278.
The problem was MBP turn on, but no charge.(Magsafe light was dim green)
The cause was no PP3V42_G3H on U6901, i retablished this and nothing happen, so after measure U6901 was not make his job; after replacement no light on the magsafe so I changed then R6929 and U6900.
And then all was ok.
The MBP has working 2 days.
And now the mac won't turn on after a sleeping mode. Have trying the smc bypass; keyboard bypass; g3hot bypass, nothing.
It's a K6 LB, I follow the power sequence and I don't have VIN in U7600 it stay on the Drain of Q7620 (12,46V) and don't have VIN in U7300 voltage stay on the Drain of Q9806 (12,46V). I have a doubt on the U7840 all the voltages seems correct but i have nothing for P3V3S5_EN_L.
It gives more idea in two brains that in one, thank you for your help.
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A little precision, what I have repaired still working. The battery is charging.
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