Steps:
Remember to try to send the commands below with and without a theoretical passwords, as we cannot be sure if the SMS password is actually inputted in the configuration.
Send SMS getapn, refer to 1.1 for information of what must be checked.
Send SMS gsminfo, refer to 1.2 for information of what must be checked.
Send SMS coords, refer to 1.3 for information of what must be checked.
Send SMS imei, refer to 1.4 for information of what must be checked.
If the device does not respond to SMS you can refer to 1.5.
More information about these SMS commands can be found in SMS commands list.
1.1 getapn
getapn allows checking if connection and APN settings are set correctly.
Response example: APN: internet User: PSW: IP1: 193.64.14.32 Port1: 7151 IP2: 193.193.165.165 Port2: 21043 TCP/UDP: 1
Note: TCP=0, UDP=1
1.1.1 APN settings:
For the device to connect to GPRS, APN settings must be entered according to the SIM card.
Note: If two IPs are configured and the „Two servers“ option is not enabled, the device can switch to 2nd server if 1st server is not available. In such case, to switch back to 1st server, you would need to restart the device by sending an SMS command reset
Note: If the client is using their own SIM cards, you may need to confirm with the client if APN settings are set correctly.
1.1.2 Connection settings (IP and Port):
To connect to a server, the correct IP address must be set. Also, the correct PORT must be chosen according to the selected data-sending protocol.
1.2 gsminfo
gsminfo - SMS message is used to get GSM and GPRS information.
Response example: ST:2018.11.23 09:27:21; OP 64901,lvl 23,LAC 123, CID: 12022, GSM; M:I 8815, R 8814, SP: 0; GPRS 0:O 2, C 0, E 8803; LK:O 5, E 7, TMO 1; RS: 14; P 1
Important fields to check:
ST - Start Time, Date & Time (GMT) from the last FM device reset/power ON. If the Start time is starting with the 1970 year, it means that the device has no GPS fix and the internal clock did not sync with GPS time. In such case the device will not generate any records.
lvl – represents GSM signal level, low level could be the reason for data delay. In case the level is low – check if the device is in a good coverage area. If the device is located in a known area of good coverage but the level is low – might be a physical problem/device installation place.
GPRS – Status of GPRS. There are two possible values: 0 – no GPRS / 1 – attached to GPRS. If GPRS is 0, the device cannot connect to the Internet or send data. Check if an incorrect APN may be set in the device configuration or temporary blacklist may not be enabled.
TMO - The number of server response timeout. A big number of timeouts indicates that there might be a problem from the server side (The device not receiving the ACK from the server). However, pay attention to „ST“ field, because „TMO“ field also represents the number of timeouts since the last restart. You may need to restart the device to check if the number of timeouts is still increasing. In case it is increasing, report the issue to SW (GUI- project).
1.3 coords
coords - SMS message is used to get current GPS status.
Response example: 2018-11-29 22:33, lat. 0.0000000, long. 0.0000000, alt. 0.0, sat. 0, dir. 0.00, hdop 0, state 2
Important fields to check:
Time - Current GMT date & time. The device will generate records only if it has a current timestamp. The timestamp is presented in GMT+0. If time starts with 1970... – there was no GPS fix established after the device restarted. Make sure that the GPS antenna (labeled face of the device) is facing a clear sky and without metallic obstructions in between.
Sat. - Number of satellites linked to the device at each moment. The Minimum is 3, but for accurate positioning at least 5 are necessary.
hdop - Positioning distortion. The lower the better, only values lower than 150 are considered acceptable for accurate positioning.
State - Current GPS/GLONASS state: 1-off, 2-on no fix, 3-on got the fix, 4-not responding, 5-sleep, 6- disabled.
1.4 Imei
imei - SMS message is used to get the device IMEI number. This SMS command can be used to double-check if the object is created with the correct IMEI number on the server side. IMEI is the most important information when creating an object on the server side. If IMEI is entered incorrectly, the server will not accept any data from the device.
Response example:
IMEI: 862462036839800
1.5 List of possible reasons why the device does not reply to SMS commands:
The device is disconnected from the power supply and thus cellular module is not working.
The SIM card is not active. Check the SIM card state.
The SMS command was sent with an incorrect SMS password. Check if the password matches the one in the device configuration.
The SMS command was sent from an unauthorized number. Check the valid numbers list in the device configuration.
The device is currently located in an area with no GSM coverage. You can refer to the raw data report to check how often and in what area the GSM signal level drops to 0.