Hello,
We have installed several FMT100 and FMB003 trackers on vehicles with roaming SIM cards. They worked fine for a few months and then gradually all bar 2 of them stopped sending any data to our server. We have narrowed it down to network connectivity. We have experience with these SIMs in other modems, and they can occasionally get into a state where they will not connect because the FPLMN list (cell tower blacklist) is full . Teltonika Networks gateways and modems are capable of clearing this list, allowing the device to connect again. However, it seems the trackers do not have this capability. To prove this hypothesis we moved a SIM from one of the trackers that would not send data into a Teltonika RUT950 and it connected to the internet, we then moved the SIM back into the tracker and the tracker started sending data again.
Is there any way to clear the FPLMN list in these trackers or send AT commands to the devices internal modem on start-up or at a set interval? If there is an SDK available for building firmware for these trackers, I could add this functionality to solve our issue.
Any help would be much appreciated.
Charlie