MacBook Pro 15" Core 2 Duo Models A1226 and A1260 Troubleshooting
- MacBook Pro won't turn on
- Laptop shuts off when I unplug it
- Flashing question mark on startup
- My screen looks black, but I can see very faint graphics on it
- Other problems
MacBook Pro won't turn on ¶
Your computer will not boot.
RAM issues ¶
If your computer beeps three times, there is a RAM issue. Either you have insufficient RAM to boot, or the RAM you do have is faulty. First, access the RAM and ensure you have RAM installed. If you have two chips, first re-seat them and try again. If that doesn't work, try one chip at a time to see if one of the chips prevents the machine from booting. If none of these works, you may have a bad logic board.
Bad Left I/O Board ¶
If your left I/O board is bad, you will not be able to start your computer when it's plugged into the wall. It may or may not run on battery and the light on the power adapter will not light up at all (some power adapters do not have lights, so this may not apply to your computer). These symptoms point to a left I/O board that needs to be replaced. We carry replacements for the left I/O board: 2.2/2.4 GHz (Santa Rosa) Core 2 Duo and 2.4, 2.5 or 2.6 GHz (Penryn) Core 2 Duo 15" Macbook Pros.
Bad power adapter ¶
If your battery is not charged, is completely dead or is removed from your machine, please make sure you are NOT using a 60W MacBook Magsafe adapter! A MacBook Pro is shipped from the factory with a 85W adapter and needs the full 85W to boot. The 60W adapter will keep a charged battery from draining but does not have enough juice to provide full charging functionality. If your power adapter is bad, the computer will run off a battery, but it won't charge. If your battery's charge is too low, it will be difficult to diagnose a bad power adapter. The easiest way to test this is to borrow either a battery or power adapter to test in your machine. If you have the same problem with another power adapter, your problem is most likely the left I/O board. If you have the same problem with a fully charged battery, you most likely need a new logic board.
Thermal Sensor Issues ¶
If the fans run at high RPMs, but the computer does not boot, there is probably an issue with the thermal sensors. First, ensure that the thermal sensors are plugged in. If they are, try replacing the thermal sensors. If this does not fix the problem, the logic board most likely needs to be replaced.
Bad logic board ¶
If replacing the DC & sound card and battery don't fix your problem, replace the logic board. We offer the following logic boards: 2.2 GHz Santa Rosa, 2.4 GHz Santa Rosa, 2.4 GHz Penryn, and 2.5 Ghz Penryn.
Laptop shuts off when I unplug it ¶
As soon as you unplug the computer from a power source, it shuts off
Dead battery ¶
If your battery is dead, the computer will run fine off the power adapter, but will turn off when unplugged. A dead battery can manifest itself in many forms: It may not accept a charge (this particular symptom may also indicate a problem with the logic board), the computer may not recognize the battery, or the battery may be recognized as charged but fail to power your computer when the AC adapter is unplugged. We sell new and used batteries.
Flashing question mark on startup ¶
The computer displays the flashing question mark when it can't find a bootable operating system. This could be because your OS is corrupt, the computer doesn't have enough RAM, or your hard drive is failing.
Bad operating system ¶
Try booting off an OS CD. Run Apple's Disk Utility and try to repair the disk. You could also try Alsoft's DiskWarrior. If this fails, reinstall your operating system. If you can, erase the hard drive prior to reinstalling the OS.
Not enough RAM ¶
This is quite rare. If you have insufficient RAM for your computer to boot the operating system, you may get the flashing question mark. Installing more RAM or downgrading to an older operating system will fix this. You need 128 MB RAM to run OS X 10.0-10.4, and OS X 10.5 requires 512 MB RAM.
Bad hard drive ¶
The hard drive may have been erased, corrupted, or damaged. If the hard drive has been erased, format it as HFS+ and reinstall your operating system back onto it. If it is corrupted or damaged, you need to replace it. Failing hard drives can display intermittent data corruption prior to failing completely. They often gradually get louder and start to click. If your hard drive is making abnormal clicking noises but still works, back up your data immediately and replace the hard drive. Any of our 9.5mm SATA hard drives will work in your computer.
My screen looks black, but I can see very faint graphics on it ¶
Symptoms of this are a dark screen, but everything else seems to be running. If you get in close with a flashlight, you can usually see the image faintly.
If your backlight isn't working, the inverter may be bad. Other parts that may be bad are the display or the logic board. If your backlight fails intermittently while moving the display, the problem is with the inverter cables. Otherwise it is impossible to test for damaged parts without replacing them one by one. If you are comfortable taking apart the display assembly, replace the display inverter first, and then replace the LCD. If you are not comfortable with this, you can replace both parts at once by replacing the display assembly. We offer the following displays: 2.2/2.4, 2.5 or 2.6 GHz (Penryn) Core 2 Duo and 2.2, 2.4 or 2.6 GHz (Santa Rosa) Core 2 Duo. If this still doesn't solve your problem, you need a new logic board.
Other problems ¶
If you lose firewire or ethernet, the only thing to blame is the logic board. Because there are many components of the logic board, many possible symptoms indicate logic board failure. Any one of these components can fail and leave the others intact. If you lose audio or USB on the left side of the machine, the left I/O board is to blame and must be replaced. Loss of USB on the right side requires the replacement of the logic board. If you lose the use of another component of your computer, such as the display, battery, or even power, and replacing the apparently non-working part didn't fix the problem, it is possible that the logic board may need to be replaced.
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