A1502 2013-2014 13” MacBook Pro Retina
|Random crashing||If bad SSD, bad SSD. If not bad SSD... no answer.|
|Not turning on, power button not working||Ribbon connector to keyboard bend/dirty/broken (bend back/clean/replace)
Example: https://www.youtube.com/watch?v=QnowcxcO2-0 (second repair, ribbon connector bend/dirty)
|No power, PPBUS_G3H 4 V instead of 12.56 V||U7100 ISL6259 bad, shorted current sense resistors R7121 and R7122 to ground through the U7100.|
|No power.||Major corrosion around U7100 (ISL6259) area. U7100 area and Thunderbolt T29 Boost Regular cleared, corrosion removed and replaced. Video Source: https://www.youtube.com/watch?v=EV1t85Q8vqM|
|No power, 24–25 mA current draw||
|No power, 180 mA taken||Corrosion at U1950
Example: https://www.youtube.com/watch?v=X2UlXmMMn6Y (replaced U1950, capacitor and resistor)
|No green light on charger||
Example: https://www.youtube.com/watch?v=FlaUiYB9FbM (U5110 (chip responsible for SMC_RESET_L) not working)
|Battery not recognized||First, try a known good battery.
If it doesn't work, check PPBUS_G3H. If it is 12.23 V, the SMC is not communicating with the battery on its data line, either because the SMC is bad, or because the pull-up resistors on the data line are bad. On rare occasion U7100 can pull down the data lines. There is a shared data line between the battery, SMC, and ISL6259(U7100). If PPBUS_G3H is 12.56 V, then you probably have a bad battery.
|No backlight||Make sure the issue is no backlight, and not no image!
Example: https://www.youtube.com/watch?v=O0_0YtdwgF0 (Repaired all corrosion including: LED driver replaced, SMC reflow, Thunderbolt chip replaced, screen connector cleaned and connections resoldered, several corroded components in memory area and screen power area replaced, jumper wire for screen backlight output)
If the screen is shorting the backlight to ground, you can fix the screen if the capacitor/connector on the screen is bad, it just sucks to do. But it is the only option since this screen is no longer available.
You can fix the screen if the capacitor/connector on the screen is bad, it just sucks to do. But it is the only option since this screen is no longer available.
When you find that 5 V is still missing on L8300 and LCD_PWR_EN is missing on U8300, do not chase. 99% of the time this turns out as a no fix, usually bad iGPU or MUX communication issues.
|Running slow/fans high||The machine running exceptionally slow with the fans spinning fast denotes a sensor issue. When a sensor is off, and it thinks the voltage/amperage is too high/low somewhere, or that the temperature is too high/low somewhere, it will clock the machine down and cause the fan to run at max RPM. You have to use a tool that reads sensors like hwsensors, or boot into a Linux distribution to check your sensors, then chase down the circuit responsible for that sensor using the schematic/boardview. If all sensors are off, this usually points to an issue with the SMC or PP3V3_S5_AVREF_SMC.
|19.5 V 100–200 mA on charger||As usual check PPBUS_G3HOT, PPVRTC_G3H, PP5V_S5
PP5V_S4 is 0 V (problem here)
C7320 has corroded pad so U7320 had no input on pin 6 so no Vcore was being produced on one of the power phases.
Redoing the corroded trace with a jumper wire and replacing the U7320 chip solved the problem.
|18.5 V 150–200 mA on charger||
No keyboard backlight
On this video the keyboard backlight connector is destroyed https://www.youtube.com/watch?v=PCJfa73GFOU
|variable current and intermittent fan spin, 820-3476||
Corrosion in U1950 area and corrosion at JTAG connector.
On this video the U1950 chip was replaced and a jumper wire ran, JTAG connector bulldozed off board. U1950 allows other signals and power rails to turn on the computer. Example: https://www.youtube.com/watch?v=yGDURMxwzt8
|Will not run off of a known good battery, but can see the battery and identify its health within the operating system using coconutbattery||Check R7005. If blown, PP3V42_G3H will not be present when running off the battery, but will be present when running off the charger.|
|80 mA, machine does not turn on.||Corrosion at U1900 RTC (Real Time Clock) circuit
|Green light on charger, fan runs full speed, machine does not turn on.||Measure voltage on inductor L7310 (CPUVR_PHASE1) located just to the left of the CPU. Should be 1.85–1.95 V
If voltage is missing check for corrosion on other side of the board (in the location where the CPU is positioned but on the back of the board) around C1212. Some capacitors including C1212 could be shorted to ground but that isn't the cause of the fault. Clean up the corrosion first. Check for hot parts using voltage injection and a finger.
In this case it was U8030 TPS22924 3.3 V S0 switch that was shorted and removing the part cleared the short. Replace with good part, problem solved. Example video for this repair: https://www.youtube.com/watch?v=C9Qb32XtROE
Note this repair also applies to the A1502 2015 model but the parts will probably have different U locations.
|No power, cycling between 20–60 mA. Rails from S5 to PP1V5_S0 pulsing.||Short on PP5V_S0_AUDIO_AMP_R (C6422 on 820-3476). PP5V_S4 reads shorted as it is connected to PP5V_S0 via 5 V S0 switch.|
|USB ports not detecting drives||For left port on logic board check for 5 V at L4605. If low or non existent check for PP5V_S4 at pins 2 and 3 of U4600. If that VIN is OK check for USB_PWR_EN at pin 4. If that is low try removing U4600 and rechecking USB_PWR_EN. If it comes back up to ≈3.3 V then replace U4600 and recheck for 5 V at L4605. This obviously doesn't cover all possible scenarios but it is one.|