Hard Disk Drive Fault Symptoms
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Faulty Hard Disk Drive.
The statistical probability is that as a computer user you will at some point in your life experience a computer that has a faulty hard disk drive. In order to determine the nature of the fault the following symptoms provide a basic idea of the problems and the remedial work involved in recovering your data.
Hard Disk Drive Not Recognised by Computer.
The fundamental purpose of the BIOS is to initialize and test the computer system hardware components and to load the operating system (OS). The BIOS also provides an abstraction layer to interact with the keyboard, display and other I/O devices.
If the faulty hard disk drive is your primary drive containing your operating system and the computer fails to boot and shows an error code then it is highly likely that your hard disk drive has failed. Typical of error codes associated with a failing or faulty hard disk drive are:-
80H Drive Failed to Respond
AAH Drive Not Ready
If the faulty hard disk drive is your secondary drive or a portable hard drive connected to a USB port then a fault log will be provided by your operating system. If your hard disk drive is not recognized by either the BIOS or OS then the fault is likely to be a consequence of an electronic or mechanical failure hard disk drive component failure.
Hard Disk Drive Not Spinning
If your hard disk drive is not receiving power then the motor that rotates the platters will not spin up. To check to see if your hard disk drive motor is spinning and therefore receiving power, follow these simple steps:
Power down and unplug your computer. Open the computer case or remove the hard drive cover and re-connect and turn on the system. You can then feel if a hard drive motor is spinning by gently placing your hand on the top of the hard disk drive cover. If you feel a gentle vibration and can hear a slight whirring noise this will be a general indication that the motor is receiving power and spinning. If your hard drive motor spins and the drive mechanics are not making clicking, buzzing or grinding noises then this can be an encouraging sign that the hard drive platter recording media where your data is stored may still be accessible and in an undamaged state.
A condition referred to as “stiction” , the head ceramic becoming stuck to the surface of the hard disk platters that prevents the motor from spinning. This condition will result in the hard drive making a beeping or buzzing sound. Click here to find detailed information regarding WD hard disk drive beeping noises.
nb:-Only undertake work on an opened computer under the supervision of a qualified technician.
In a hard disk drive data is stored in thin, concentric bands written to rotating platters, these are called data tracks. A hard disk drive head assembly whilst in one position can read the information stored in these data tracks. There can be typically thousands of tracks formatted across the surface of a 3.5-inch hard disk platter. Formatted sections within each track are called sectors. A sector is the smallest physical storage unit on a disk, and contains typically 512 bytes of binary data stored as a magnetic pattern representing simple ones and naughts.
Hard disk drives reserve a small amount of the track data areas for head positioning and motor speed data parameter information. These parameters are used to control the basic operation of the hard disk drive and are written during the manufacturing process and are not available to the operating system. The hard disk drive controller electronics will use this information to fine tune the head assembly positioning as the read and write heads move from one data track to another and also use the parameters to regulate the spindle motor speed tolerances.
Precision track co-ordinates are held in the hard disk drive controller electronics firmware. When the hard disk drive is powered and the motor turns the hard disk drive controller program instructs the head actuator assembly to move from its home position to a track co-ordinate position. Here it expects to read pre-programmed information concerning the hard disk drive parameters, the device configuration and correct operation. Failure to read this information will result in the actuator rapidly returning to a home or invalid co-ordinate position, an error code being output and a number of abortive re-tries. The hard disk drive read write head assembly actuator positioning is under the control of a powerful dampening magnet. A return to home position and a retry results in a sharp clicking noise and is indicative of either corrupt recording media or an electrical failure of the read write head assembly components. Hard disk drive platters spin at speeds in the order of 7500 rpm and read write head movement from one track to another is extremely rapid and in some instances involving adjacent data tracks is barely visible to the human eye.
If your hard drive motor spins and is not making clicking, buzzing or grinding noises then this can be an encouraging sign that the hard drive recording media maybe accessible and undamaged. As mentioned previously you can feel if a hard drive motor is spinning by gently placing your hand on the top of the drive case. A gentle vibration will indicate that the motor is receiving power and is turning.
Click here for further general information regarding Clicking Hard Disk Drives.
Hard Disk Drive Bleeping and Buzzing Sounds.
If following the application of power a beeping or buzzing sound is produced then this would indicate that the spindle motor is jammed or is held fast by the read write head transducer becoming welded to the platter surface. In the absence of permanent platter surface damage this problem may be solved by releasing the weld and substituting the damaged read write heads for a good matched component replacement. This work needs to be carried out in a clean air environment.
Hard Disk Drive Head Crashes.
A hard disk drive head crash is a term used that describes the effect of the readwrite heads making continued and damaging contact with the hard disk drive platters. This continued contact causes a scouring or scratching to the smooth surface of the platters. In a minority of cases this will remove the magnetic coating material of the platter leaving a visible ring, however in the majority of cases the ensuing damage will not be visible to the naked eye. When the magnetic material component of the platter is damaged there is nothing that can be done to recover data that was written to those track areas of the hard disk drive. The damage to the smooth surface of the platter caused by a head crash will affect the fine operational tolerances under which the head assembly slider flies above the platter surface and normally precludes the introduction of a compatible replacement part rendering data stored on any un-damaged tracks unrecoverable by standard data recovery techniques. Advanced data recovery techniques involving precise control of the head positioning in relation to unaffected data tracks may be possible. These techniques however involve special capital intensive tooling that operates independent of the integrated hard disk drive controls. The time consuming operator costs and analysis involved will in most cases be cost prohibitive in relation to the value of the stored data.
Click here for more information regarding Hard Disk Drive Head Failure.
Things To Bear In Mind.
There are a number of important things to bear in mind regarding dealing with faulty hard disk drives;
Static electrical discharge may cause electrical component damage, so don’t handle a damaged hard drive without taking anti-static precautions.
A hard disk drive is a sealed environment whose moving components operate in filtered clean air. Particulates in the normal atmosphere of a room will cause permanent damage to the read write head transducers. Do not under any circumstances open a hard disk drive, leave this to a professional data recovery company with adequate facilities and technology.
Electronic controller and mechanical assembly operate as a parametric matched pair. Do not swap the electronics controller card for another as this my constitute a risk of damage to the data stored on the hard disk drive platter , especially if the revision number of the PCB is different.
Large volume production and increasing performance demands means controller card integrated circuit component count is now in single figures. Faulty hard disk drives therefore exhibit very few discernable physical fault symptoms. Diagnosis and repair of latest hard drive technology is only possible using specialist data recovery tools and test equipment and the services of a professional data recovery company.