Just in the past two weeks I had to replace three failed hard drive cables in three different MacBook Pro (13″ Mid 2012) laptops. I’m not sure if there is a known issue with these cables but the failure rate seems to be unusually high.
The cable failure might have one of the following symptoms that look like a “regular” hard drive failure or OS corruption:
– The laptop boots to a flashing folder with a question mark.
– The Apple logo appears on the screen but the OS doesn’t boot any further.
– It gets stuck at a white screen and doesn’t boot any further.
In order to troubleshoot this problem you will have to go thought the following steps.
1. Remove the hard drive and test it on a PC with HDTune utility. The free version should be enough to run the Error Scan test on the drive and make sure it’s not failing.
Alternatively, you can test the drive on another working Mac with the Drive Genius utility. Again, the demo version should be enough to scan the drive for bad blocks.
You can connect the hard drive to another PC or Mac using an external USB enclosure or SATA to USB cable.
2. Test your MacBook Pro with another known good hard drive and try reinstalling the operating system.
If the laptop fails the same way with another hard drive, most likely you have a failed cable and it has to be replaced.
Instructions for replacing the hard drive cable.
Remove two screws securing the rear mounting bracket. Remove the bracket.
Lift up the hard drive from the case and disconnect the SATA cable.
Remove two screws securing the cable.
Remove two screws securing the front mounting bracket.
Unplug the cable from the logic board.
Peel the cable off of the case and remove it.
You can search for a replacement cable using the part number printed on the original cable: 821-1480-A.
UPDATE: The newer cable part number is 821-2049-A or 923-0741. If you are replacing it, find the newer one.
There’s the tricky part. The new cable has the IR sensor attached to it but the sleep LED is located on the front mounting bracket.
It will be necessary to disconnect the failed cable from the sleep LED and here’s how you do it.
Work carefully, the cable connector is very small. Lift up the right side of the cable retainer until it opens up at a 90 degree angle.
Pull the sleep LED cable out of the connector.
Start separating the IR sensor from the mounting bracket. It’s glued with double sticky tape.
Peel the IR sensor off.
Now you can glue the new IR sensor to the bracket, install the sleep LED cable into the connector and lock it.
Make sure the cable seated properly, all the way down into the connector.
Finally, install the new cable into the laptop and connect the hard drive.
Do you have the same problem with your MacBook Pro 13-inch Mid 2012 laptop?