Frequent Answers and Questions
(1) Check if the SIM card is valid
(2) The SIM card is placed correctly in the slot
(3) The connection of the GSM antenna is OK
(1) The SIM card inside the system has no credit
(2) The SMS instruction is not in correct format
(3) The mailbox of the user's mobile is full .
(1) Please place the GPS antenna outdoor
(2) In cloudy or under ground areas, it is a little hard to get the GPS signal, and the GPS coordinate might have some errors.
(3) Please check the connection of the GPS antenna.
(1) Check that the format of the instruction ******STP is correct.
(2) Replace another relay to test.