RB900SG Troubleshooting
Z Elproma Wiki Knowledge Base
No connection with the modem
If there is no communication with the modem take the following steps:
- check all external connections with the modem (serial interfaces, USB, power supply).
- check that the power supply is correct (see Power supply).
- check that the COM port is correct.
- when connecting the modem with the meter, check whether the meter is powered and the POWER diode in the modem is on.
No connection/communication with the modem
If there is no communication with the modem take the following steps:
- Check all external connections of the modem (RS-232 or USB, Power supply)
- Verify if the power supply is correct (see Power supply)
- Check if the COM port is correctly parametrized
- Check if the program used for communication works properly and if there is no other program interfering. If yes, close the interfering program.
Receiving ERROR message The modem answers ERROR on AT command in the following cases:
- The syntax of typed AT commands is incorrect – check the command syntax in [1]
- Parameters of typed AT command are incorrect - type AT+CMEE=1 for enabling wide description of error which occurred. The response now will be in format:
ERROR +CME ERROR: <err> where <err> is a description of the error which has occurred.
Receiving NO CARRIER message There are some common cases when the modem answers NO CARRIER:
- If a data/voice/fax connection cannot be established
- Right after hanging up the data/voice/fax connection
- If there is no connection with the network – check antenna and registration status (see Network registration)
- If there is no power supply (see Power supply)
- If modem answers NO CARRIER, you can check extended error code using AT#CEERNET command. A list of codes can be found in AT commands reference guide manual.