NFF - not fault found – faults caused by exterior factors


Our repair service sometimes receives devices which are operational; however, their users report issues relating to their operation. In many such cases, the cause of issues described in the issue report may be external factors not connected with the device itself. The following are the most frequently reported issues along with advice on what to do in the case of their occurrence.


Device battery operation time

It is worth bearing in mind that the battery life is affected by — apart from the battery parameters — other factors such as usage intensity, device settings or network conditions. Here is some advice concerning methods of extending the device operation time.

Running applications

Applications have significant impact on energy usage. The most frequently used applications which can shorten the device operation time include: Facebook, Messenger and Snapchat. If the device operation time was reduced dramatically after installing a new application, we recommend its removal.

Some applications, even after being closed, can still work in the background, downloading data and connecting to the Internet. It is good to ensure that applications which are not needed in a given moment are correctly turned off. On Android devices, applications can be effectively turned off via the Settings/Application Manager option — select an application running in the background and stop it.

Data transmission

Please note the running time of Wi-Fi, Bluetooth, GPS, location services and NFC. Functions which are not currently in use should be turned off. Functions which fulfill the same tasks should not be doubled — e.g. if Wi-Fi is on, you can turn off the 3G/LTE data transmission. Another good idea is to limit synchronisation of email and social media accounts as well as automatic update downloading.

Local network conditions

The signal strength of the Operator’s network depends, among others, on the degree of urbanisation of the area and distance from the transmitter. Moving over an area — in particular when driving a car or staying in a location where a given service has limited range — can lead to range temporarily fading. This concerns primarily the LTE and 3G services, which are poorly developed in certain locations. If the device operates in automatic mode (LTE/3G/GSM), which enables switching between individual modes, and the range keeps fading, the device will keep switching automatically, which will cause increased power consumption and the battery will run out of power more quickly. During a journey or while staying in a location with poor LTE range, when connecting to mobile Internet, switch to 3G and if that does not work — to GSM mode.

Device settings

You can extend battery life by reducing the display brightness and backlight time, removing animated screen savers and backgounds. Most devices also allow for the use of battery saving mode.

We understand that it is smartphones’ different functions that determine their usefulness. This is why, during intense use of the device, we recommend getting a PowerBank — an external battery which extends the device operation time. Before purchase, make sure that the PowerBank has the appropriate certificate and is compatible with the device.

IMPORTANT! The battery is a part of the device which is subject to natural wear process. With time, its parameters may gradually deteriorate. In the case of long-term battery use, it is recommended to consider its replacement.


Charging the device after the battery runs out completely

If the battery runs out completely, after connecting the charger, the charging process may not commence immediately. Wait several minutes before the charging process is initiated. We recommend charging the battery before it runs out completely, when a warning about low power level is displayed.

Charging the device using a USB cable connected to a computer

The device charging process using a computer USB cable can be disrupted by the User’s activity. In certain cases, the device’s power demand can prove greater than the maximum USB port current, which amounts to, respectively, 500 mA (milliamperes) for a USB 2.0 port and 900 mA for a USB 3.0 port. Therefore, in order to quickly charge the device or in the case of active device usage during the charging, we recommend always using the original wall charger. When connecting the device to a computer using a USB cable, the User can use the data transfer function as well as other device functionalities. In such cases, the charging process can take more time; if the workload is high, the device may run out of battery.

Inductive charger

Wireless chargers — so-called inductive chargers — are becoming increasingly popular in the market. Unfortunately, many of them do not conform to the Manufacturers’ standards. Using a non-original charger can be inefficient or even lead to seriously damaging the device.

Non-original chargers

The efficiency of non-original chargers can be several times lower than that of the Manufacturer’s original charger. Their use can extend the charging time and, in extreme cases, cause damage to the device. We recommend using original accessories.


No connection

If you can’t make calls on your phone – it may be due to the device being blocked by the Operator. We would like to remind you that if you don’t repay installments for a device bought on credit or you have unpaid invoices, the Operator may block the device. Operator’s blockade will result in the inability to make calls, also on the other Operators’ SIM cards. The device will pass the service tests performed with the use of the Manufacturer's software, because it is not damaged. Therefore, in the event of such a defect - especially if the device was already send to the service center and the fault has not been confirmed, we recommend to check your payments. If the bills are not paid- please get in touch with the Operator and check if the device has been blocked. If you bought a used device – e.g. via Internet and you have no way to check from which Operator it was originally bought- please contact the Seller.

Crashing / Spontaneous shutdown / Slowing down

Device crashing, spontaneous shutdown or slowing down frequently results from the User running additional applications. If any of these occur, first remove recently installed applications or format the device’s memory card.

Remember that it is recommended to switch the device off from time to time in order to reset applications and processes running in the background. If the issues persist, it is recommended to perform a Hard Reset of the device (according to the recommendations included in the User Manual) in order to free up the device’s memory and restore its factory settings.

IMPORTANT! Since Hard Reset causes removal of contacts, messages and other data from the device, remember to create a backup copy of data before performing this operation. Most Manufacturers offer tools which allow for making a backup copy of data.

A copy of data can be created using tools provided by the device Manufacturer. Examples of such solutions are presented below. In the case of doubts, it is recommended to call the Manufacturer’s hotline.

Poor range (telephone calls and internet connection)

The reason for inconvenience related with poor range can be damage to the SIM card. We recommend performing a test of the SIM card at the Operator’s Showroom.

Issues with range can also be caused by local conditions of the Operator’s network.

Another reason for issues with range can be the phone operating in dual mode and poor LTE/3G range (for more information about this topic, see the item dedicated to Local network conditions).

Poor reception or connection

Mobile telephone operation depends not only on its parameters but also on external factors. Major factors which affect the connection quality include:

  • network signal strength,
  • distance from the Operator’s BTS station (network transmitter),
  • obstacles which disrupt signal (electromagnetic wave) dissemination between the transmitter and the User’s device — including the landscape and buildings, adverse weather conditions, proximity of a high voltage source or an electromagnetic field.

The phone’s operation can also be disrupted by covering the antenna with one’s hand since the antenna is typically located in the bottom part of the device, at the back (for details, see the user manual) or using flash stickers which consume considerable amounts of the energy emitted by the antenna.

Distorted sound / lack of sound

Deterioration of the sound quality may be caused by:

  • dirt in the microphone or speaker disrupting its operation (this is why it is important to properly protect the device against dust and other contaminants),
  • use of non-original accessories (e.g. a case which covers the microphone/speaker openings),
  • factors described above, associated with the conditions of the Operator’s network.

Incorrect touchscreen operation

The touchscreen may not work properly due to:

  • use of protective film or tempered glass without the Manufacturer’s certificate, intended for another device model or incorrectly applied (these elements can cover sensors built into the touchscreen)
  • use of the touchscreen in gloves not intended for mobile device operation, with wet hands or moisture penetration into the display (even in the case of devices with increased water resistance — IP certificate).


GPS involves determining the location based on the signal received from the satellite. For this reason, GPS operation may be affected by:

  • urban obstacles — buildings, tunnels, underground passages,
  • adverse weather conditions,
  • proximity of a high voltage source or an electromagnetic field.

Signal loss in presence of the above factors does not mean the device is functioning incorrectly.

IMPORTANT! To use GPS, turn the “location” option on in the phone settings. If this function is disabled, GPS will not find the User’s location. It is also important to make sure that the User is not covering the device’s antenna with their hand or a car/bicycle holder (information about the antenna location can be found in the user manual). Many devices offer functions which support the operation of location services, e.g. built-in device sensor, location using the mobile telephone network (AGPS), advanced GPS. Information about these functions is included in the user manual.