Is repairing my LCD monitor worthwhile?
By: Simon Blohm
Translation: Siobhán Hayes
When it comes to the seemingly simple question of whether the repair of an LCD monitor is worthwhile after any guarantee on the side of the manufacturer has expired or whether it is more intelligent to buy a new model and dispose of the old one, there are various factors to be considered and weighed up with regard to the model and the subjective sensitivity of the owner.
First, the cause of the defect in an LCD monitor must be established or an expert must be engaged to establish this cause. Often, an estimate of costs for the repair is very inexpensive or may even be free of charge.
The most common source of faults in LCD monitors: The "backlight"
Faults in LCD monitors can be caused by various error sources. Depending on the type of fault, the outlay for the repairs and the required replacement parts, it can be decided whether repairs are worthwhile or whether it would be better to buy a new model.
The most frequently occurring fault in an LCD monitor in terms of percentages is a failure of the backlight. This fault source can even be recognised by holding a source of light (for example, a torch) in the direction of the apparently dark LCD monitor and checking whether the image to be displayed is faintly visible. The cause of the fault in this case is then clearly a failure of the backlight, i.e. the integrated CCFL tube (cold cathode fluorescent light). Other symptoms which indicate a fault with the backlight in addition to the dark screen are fluctuations in the brightness of the screen as well as a reddish, dark image.
As well as a fault with the CCFL tube, the inverter board, which monitors the power flow to the CCFL tube, may also be defective. When the power flow deviates from the target value, the power supply is shut off. This is visible in that although an image appears briefly after the monitor is switched on, the monitor switches itself off several fractions of a second later. If such faults arise in CCFL tubes or inverter boards, repair is worthwhile in most cases, since it usually costs less than a new model or than the current market value of the monitor. For example, a CCFL tube costs about 25 Euro depending on the diameter or type, a modern inverter board costs less, at about 15 to 20 Euro.
Inverter board of an LCD monitors.
Simple sources of faults, which are often overlooked
In addition, the fault need not always be with the LCD screen, but may also have completely different, much simpler causes. Often, it happens that a seemingly defective monitor is disposed of although the source of the problem does not lie with the monitor itself, but instead has completely different roots. Examples of this include defective HDMI or VGA cables or a faulty plug. A problem with the PC itself, especially a fault with the graphics card or graphics card port or the driver software used may also be the cause of a seeming fault with the LCD monitor. The aforementioned accessories can be bought cheaply and restore the functionality of the LCD monitor.
Other "defects", which may arise with an LCD monitor include what are known as pixel errors. These are visible in that one or several pixels glow continuously or are black. This is more or less pronounced depending on the position of the pixel error. Pixel errors are tolerated with certain tolerance levels in production by the manufacturer as per ISO 13406-2.
For an LCD monitor with a screen resolution of 1.400 x 1.050 pixels, for example, two pixels may glow constantly, two may always be black and seven sub-pixels may be defective when the model is delivered. The number of pixel errors on the screen does not accumulate with time, so you should check the screen for errors of this kind directly after buying it. Once the guarantee period has expired, the manufacturer will not take responsibility for such repairs and the customer has to cover the cost of a new LCD panel (screen).
In practice, this process is generally not worthwhile for an LCD monitor, since a new LCD panel can be quite expensive depending on the manufacturer and size and it would almost be possible to buy a new model for this amount when the costs for the repairs and collection are added. Thus, should problems with pixel errors arise after the warranty has expired, it is advisable to dispose of the old monitor or learn to live with the defective.
Here, the situation is similar for damage of any kind caused by thermal or physical damage to the LCD display. Examples include scratches, "blind spots" on the LCD screen or similar. Only for LCD screens on laptops is it possibly helpful to have the screen changed. However in practice, this depends on how old the laptop is and how high the cost of a new device with comparable specifications is. Thus, for example, if a six-year-old laptop is defective for reasons that are unknown, one is generally much better off disposing of it and purchasing a new one, since the cost-benefit factor is generally not satisfactory for such a model. However, if there is a problem with your high-end designer laptop, which is just two years old and cost a small fortune to buy, you should consider a repair. This is how one should decide not only for LCD screens in laptops but also for LCD monitors in general.
The cost-benefit factor
The cost-benefit factor plays an important role and should first be explained by an expert. Experts can generally find the cause of the problem quickly and easily and provide an estimate of the costs for any repairs including the required replacement parts. Thus, the customer can then decide on a case-by-case basis whether repairs are more sensible than getting rid of the old monitor. However, one thing is certain: Before making a decision to dispose of the apparently defective monitor, you should find an expert and take some advice, since the problem is often due to small issues such as a defective component which can be replaced quickly and inexpensively.
Finding the cause is the highest priority
If you know the precise cause of the problem, it is easier to weigh up how to proceed. It is not possible to provide a blanket answer to the question as to when repairs to an LCD monitor are worthwhile because of the complex, delicate structure of the models- this is the nature of the thing. The only important thing is that you find the source of the problem and then decide whether the repairs are worthwhile compared to the cost of disposal and a consequent new purchase.
Where can I get my monitor repaired?
Below are three Internet addresses which you can use as a first point of contact. However, as a rule, there will certainly be an authorised repair centre near you.