Error codes 2 or 3 is flashing on the SMS Lite status indicator

These flash codes indicate a problem with trying to initialise the modem module. Removing the lid to the device will allow the user to view the LED indicator on top of the modem module itself. These problems usually require the unit to be returned for service but there are some checks that can be done beforehand If the indicator is on or flashing then this usually (not always) indicates that the modem module is functioning. If it is flashing then the modem has actually registered on a cell tower so the fault probably lies in the interface between the daughterboard and the motherboard or with the SIM. Error Flash code 2 can be a problem with: The power to the module had failed you would not see the indicator on the modem module in that case. If there is also no indication on the status LED then it is likely a power problem. If the indicator on the module does work the voltage may be just low in which case it will need servicing. Other issues may be a hardware fault such as a dry solder joint. If the SIM is faulty or not configured correctly by the Mobile Network Operator then it may prevent communications to the modem module so it might look like a module problem when in fact it is a SIM problem. Trying using the SIM in a phone to send a SMS message, if that does not work then it is the SIM at fault not the device. Visually inspect the modem module to see that it is correctly plugged into the socket on the motherboard Error Flash code 3 (and sometimes code 2) commonly occurs when: The contacts on the SIM are dirty or the SIM is incorrectly inserted, clean the SIM with a solvent like isopropyl alcohol. Me sure the SIM is and any breakouts for the smaller SIM sizes are intact. The SIM is preventing digital communications between the modem and the main processor (daughterboard and motherboard). Try the SIM in a phone. There is a hard fault with the connections between the modem and the processor. Visually inspect the modem module to see that it is correctly plugged into the socket on the motherboard