Hard Drive Failure? Hardware test OK

The drive is dead. if you purchased the extended AppleCare Protection Plan, Apple will replace the drive at no charge. If you didn't it's time to go shopping for a new drive.

Clinton

Welcome to the Apple Support Communities

Apple Hardware Test checks the sensor and the fans of the hard drive, but doesn't check the hard drive integrity. To do it, you have to use Disk Utility.

If the hard drive doesn't show up on Disk Utility, it means that your hard drive is damaged or that the hard drive connector to the logic board is damaged. The best thing you can do is to buy another hard drive, for example, in OWC, and install it yourself. Then, erase the hard drive with Disk Utility and reinstall OS X, so your MacBook Pro will be running again.

If your MacBook Pro doesn't detect the new hard drive (I doubt it), then there's a problem with the logic board, so you will have to take the computer to an Apple Store or reseller and get ready for a very expensive repair

I don't think that your logic board has got a problem (if it is, Apple Hardware Test should have shown an error). If it shows that everything is OK, it means that your logic board is perfect, so just install another HDD or SSD.

SSDs allow you to increase dramatically the performance compared with your actual HDD. They are more expensive, but if you want speed, you should install one

Here's my one and only user tip about upgrading to a SSD - https://discussions.apple.com/docs/DOC-4741.

They are very expensive when you consider the cost per gigabyte. That said, they are also very fast and as simple to install as a hard drive. Personally, I've had a 512GB Crucial m4 series SSD in my MacBook Pro for 11 months and don't see how I ever got by without one (and when the 960GB Crucial M500 ships, I'll be buying one of those). But if you're going to get one, try to do so soon as the price of memory is projected to go up this year.

You should also take a look at fast, high-capacity hard drives. I've three of the HGST 1TB 7200rpm SATA III drives, two of which I purchased through OWC. It's the fastest platter-only 1TB drive on the market and would 'play well' with your 2011 model - see http://eshop.macsales.com/item/HGST/0J1TB7200/.

Either an SSD or a good, fast hard drive would meet your needs, I think...

Clinton

Over a very large sample of drives, these drives are very reliable. But you do not have a very large sample, you have ONE DRIVE. Anything could happen.

Laptop drive are subjest to extreme stress and vibration because they are moved around. Stuff happens.

The test of whether a drive has died is this:

A Drive that will not tell Disk Utility BOTH its Make&Model and a reasonable size/capacity cannot be initialized or repaired. If its cabling is not damaged, the drive has died.

If it will still communicate those items, there are a few last ditch things you can try.