-When power on bought the GREEN and the RED LED light up.

-If the RED LED blinks for 32-36 times then it means that there is no response on the CAN communication line, this means that the cable isn't connected or the tachograph doesn't have CAN interface.

-If the RED LED blinks oddly for a few times (FW 1.4.11-1.4.17) or 3 times that means that the Remote Download wasn't enabled on the tachograph.

-If the CAN is connected properly and the Remote Download is enabled then the green led will blink one time (from FW v1.4.11) if error the RED LED will blink and restart,

-If the RED LED blinsk for 10-11 times then it means that the SIM card isn't inserted or the connectors are dirty and needs to be cleaned with some alcohol.

-If the RED LED turns on it means that it is trying to connect to the server.

-If the RED LED turns out after a while (10s-60s) and back to RED then there is something wrong with the SIM card APN.

-If the GREEN LED turns on it means it is connected successfully to the server.