Dear community,
this is my very first post, I am quite new to macbook repairs, and I am excited:-)
I have a 2011 MacBook Air 13' that does not power on. No fan spin, nothing.
Here are the specs:
MacBook Air Mid-2011
CPU: 1.7 GHz Core i5 (I5-2557M)
Model: A1369 (EMC 2469)
RAM: 4 GB
VRAM: 384 MB
The first question:
Unfortunately, it came with a 'fake' power adapter which seems not to talk to the computer. Sometimes it does show green light immediately after connecting it to the board, sometimes it shows green light after a few seconds, sometimes it doesnt show a green light at all. But it has never shown red light.. I thought that the DC-IO-Board may be faulty, but I tried with another DC-IO-Board from another Macbook Air with the same specs - still nothing. The second Macbook Air has the 3-beep-fault, but at least it has a fan spin. Due to this, I assume that its DC-IO-board is good. Hence, I assume that the first Macbooks IO-Board is okay, too.
I do have an original MagSafe from 2011, but it is the one for the Macbook Pro, giving 16.5 V/3.65 A. Can I use this one on my Macbook Air to test? On the Air's cover there are 14.5 V/3.1 A specified only.
The second question:
PPBUS_G3H = 8.36 V
According to the schematics, it should be 12.8 V, but the other Macbook with the 3-beep-failure also has 8.36 V on PPBus_G3H. Can I assume PPBus_G3H to be okay then?
Third question:
While measuring some rails, I noticed:
PPVIN_SW_T29BST = 0.14 V
But in the Rossmann forum I have read that this has to do with thunderbolt, hence I assume that I dont have to care about this right now.
Fourth question:
I also noticed:
CPU_RESET_L = 0.14 V
On the other board this was 1 V. CPU_RESET_L is made by U2780 with:
PP3V3_S0_RSTBUF = 3.3 V
PLT_RESET_L = 0.0 V
..C2680 and R2680 are not shorted to ground.
PLT_RESET_L is sent out from the PCH, hence I wanted to check if the PCH is powered on:
PP3V3_S5_PCH_VCCDSW= 3.3 v
PPVRTC_G3_PCH = 3.3 v
PP1V05_S0_PCH_VCC_CORE = 1.05
PM_SLP_S5_L = 3.34 v
This seems good. Hence, I assume that U2780 is broken.
:::Some other rails that I measured:
PPBUS_S0_LCDBKL = 8,36 V
PPBUS_S0_VSENSE = 8,36 V
PPVIN_S5_P5VP3V3 = 3,3 V
PP18V5_DCIN_CONN = 14,86 V (strange?!.., as with PPBus_3GH)
PPDCIN_OR_PBUS = 14,86 V
PPDCIN_G3H_INRUSH = 14,86 V
PP3V42_G3H_REG = 3,42 V
PP3V3_S5_LPCPLUS = 3,3 V
PP3V3_S5_SMC = 3,3 V
PP3V42_G3H_CHGR = 3,42 V
PP3V42_G3H_PWRCTL = 3,42 V
PP3V42_G3H_SMBUS_SMC_BSA = 3,42 V
PP3V42_G3H_ONEWIRE = 3,42 V
PP5V_S0_FET = 5 V
PP5V_S0 = 5 V
PP5V_S0_BKL = 5V
PP3V3_S5_REG = 3,3 V
PP3V3_S5_XDP = 3,3 V
PP3V3_S5_CPU_VCCDDR = 3,3 V
PP3V3_S5_LCD = 3,3 V
PP3V3_S5_PCH = 3,3 V
PP3V3_S5_PCHPWRGD = 3,3 V
PP3V3_S5_SYSCLK = 3,3 V
PP3V3_S5_VMON = 3,3 V
PP3V3_S5_PWRCTL = 3,3 V
PP3V3_S5_PCH_VCC_SPI = 3,3 V
PP3V3_S5_P3V3SUSFET = 3,3 V
I am very thankful for any help:-)
this is my very first post, I am quite new to macbook repairs, and I am excited:-)
I have a 2011 MacBook Air 13' that does not power on. No fan spin, nothing.
Here are the specs:
MacBook Air Mid-2011
CPU: 1.7 GHz Core i5 (I5-2557M)
Model: A1369 (EMC 2469)
RAM: 4 GB
VRAM: 384 MB
The first question:
Unfortunately, it came with a 'fake' power adapter which seems not to talk to the computer. Sometimes it does show green light immediately after connecting it to the board, sometimes it shows green light after a few seconds, sometimes it doesnt show a green light at all. But it has never shown red light.. I thought that the DC-IO-Board may be faulty, but I tried with another DC-IO-Board from another Macbook Air with the same specs - still nothing. The second Macbook Air has the 3-beep-fault, but at least it has a fan spin. Due to this, I assume that its DC-IO-board is good. Hence, I assume that the first Macbooks IO-Board is okay, too.
I do have an original MagSafe from 2011, but it is the one for the Macbook Pro, giving 16.5 V/3.65 A. Can I use this one on my Macbook Air to test? On the Air's cover there are 14.5 V/3.1 A specified only.
The second question:
PPBUS_G3H = 8.36 V
According to the schematics, it should be 12.8 V, but the other Macbook with the 3-beep-failure also has 8.36 V on PPBus_G3H. Can I assume PPBus_G3H to be okay then?
Third question:
While measuring some rails, I noticed:
PPVIN_SW_T29BST = 0.14 V
But in the Rossmann forum I have read that this has to do with thunderbolt, hence I assume that I dont have to care about this right now.
Fourth question:
I also noticed:
CPU_RESET_L = 0.14 V
On the other board this was 1 V. CPU_RESET_L is made by U2780 with:
PP3V3_S0_RSTBUF = 3.3 V
PLT_RESET_L = 0.0 V
..C2680 and R2680 are not shorted to ground.
PLT_RESET_L is sent out from the PCH, hence I wanted to check if the PCH is powered on:
PP3V3_S5_PCH_VCCDSW= 3.3 v
PPVRTC_G3_PCH = 3.3 v
PP1V05_S0_PCH_VCC_CORE = 1.05
PM_SLP_S5_L = 3.34 v
This seems good. Hence, I assume that U2780 is broken.
:::Some other rails that I measured:
PPBUS_S0_LCDBKL = 8,36 V
PPBUS_S0_VSENSE = 8,36 V
PPVIN_S5_P5VP3V3 = 3,3 V
PP18V5_DCIN_CONN = 14,86 V (strange?!.., as with PPBus_3GH)
PPDCIN_OR_PBUS = 14,86 V
PPDCIN_G3H_INRUSH = 14,86 V
PP3V42_G3H_REG = 3,42 V
PP3V3_S5_LPCPLUS = 3,3 V
PP3V3_S5_SMC = 3,3 V
PP3V42_G3H_CHGR = 3,42 V
PP3V42_G3H_PWRCTL = 3,42 V
PP3V42_G3H_SMBUS_SMC_BSA = 3,42 V
PP3V42_G3H_ONEWIRE = 3,42 V
PP5V_S0_FET = 5 V
PP5V_S0 = 5 V
PP5V_S0_BKL = 5V
PP3V3_S5_REG = 3,3 V
PP3V3_S5_XDP = 3,3 V
PP3V3_S5_CPU_VCCDDR = 3,3 V
PP3V3_S5_LCD = 3,3 V
PP3V3_S5_PCH = 3,3 V
PP3V3_S5_PCHPWRGD = 3,3 V
PP3V3_S5_SYSCLK = 3,3 V
PP3V3_S5_VMON = 3,3 V
PP3V3_S5_PWRCTL = 3,3 V
PP3V3_S5_PCH_VCC_SPI = 3,3 V
PP3V3_S5_P3V3SUSFET = 3,3 V
I am very thankful for any help:-)
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