Troubleshooting (USB)

The first question is whether your phone detects that you have connected the card reader. If it does, a dialog box will pop up asking for permission to use the connected USB device. You must grant this permission for downloading to begin.

The phone does not detect the card reader

  • Some phones (Oppo, OnePlus, Realme, Vivo, Poco) automatically disable the OTG (On-The-Go) feature after a period of inactivity. Find the OTG feature in your phone's settings and configure it to remain permanently enabled.
  • Some USB adapters only support charging, not data transfer. Use an adapter that also supports data transfer.
  • The connector may not be making proper contact: the phone case may be too thick, the USB port interior may be dirty, or one of the contacts may be damaged.

The phone detects the card reader, but an error occurs during reading

You should observe whether the card download fails right at the beginning or only partway through. A typical sign of a problem is the download failing at different phases across multiple attempts.

If the error occurs at the start of the download

  • The reader does not comply with the CCID standard. Some tachograph analysis companies sell proprietary card readers under their own brand name.
  • You have not inserted a driver card. The app cannot download data from company cards, workshop cards, or control cards.
  • The card is inserted the wrong way. With some readers it is difficult to tell the correct orientation — try inserting it the other way.

If the error occurs at different phases of the download

  • The USB connection is unreliable: the phone case may be too thick, the USB port interior may be dirty, or one of the contacts may be damaged.

The phone, the card reader, and the driver card are all technical devices that can fail in many ways. If you have the opportunity, try the card reader with another phone and try your phone with another card reader — this will help identify which device is not working correctly.

We do not recommend using multi-function card readers (Smart/SD/SIM). These present multiple interfaces, and Android does not always select the correct one.

If the problem persists, contact us and send us the app's log file. You can find this function in the main screen menu.