Why GPS tracker offline

Below are the possible main reasons of vehicle GPS tracker device offline, we also provide checking way accordingly.

1.Power supply

Some drivers like to turn off the battery of vehicle during parking, or the power wire connection between GPS tracker and vehicle's power is disconnected (including be cut off by someone)

Checking the latest online data like external power and internal battery value before offline will get clear answer to this question.

2. SIM card without available credit

It is very common and is the main reason of device offline.

However, the common mistake is that the users think the SIM card has enough credit but actually the credit has run out.

- The device can reply SMS command doesn't mean the credit is enough: Device online needs the GPRS data plan. Part operators provide different packages to their customers. For example, calling and SMS are one package, the GPRS data is another package. It is logical that the device can reply SMS or the calling is normal but the GPRS data has run out.

- If the users use the M2M SIM card management platform, the situation is more complicated. The user can limit the data consumption of the SIM card. There are active/inactive SIM card, prepaid or postpaid options. Even everything looks normal, the M2M SIM card itself may have issues, especially under roaming network.

The challenge is that the GPS tracker supplier doesn't have a reliable way to judge the SIM card credit. So the users need to keep a good record of SIM card recharging. Two further steps are suggested below:

- Try to recharge SIM card if can't find other reasons of device offline

- Replacing with another proved SIM card for comparison testing

- Some types SIM card need registration. However, the challenge is that these SIM cards still can work for a period time (Eg: for around a month) even without registration. From the user's view, this device works well then suddenly offline, and can't work after the credit is recharged. They forget this SIM card need be registered.

Do the comparison testing with another proved SIM card always is the No. 1 suggestion for removing the dobut of SIM card.

- SIM card can't fit the SIM card slot well. In some countries, the SIM card's quality is not very good, or the vehicle's temperature is too high which affects the shape or touch pin of the SIM card. Finally the SIM card can't fit the SIM card slot well. The user can find that the SIM card from A operator is not working, from B operator is working. Or two SIM cards both are from the same operator but one works, the other one is failed.

3. Parameters are wrong

IP, port, APN, and the time interval are core parameters affecting the online.

We developed SMS command below to retrieve current parameters.

000000,C06 (000000 is default SMS command password)

Below is an example of 000000,C06 reply

C06,862273048221154,194.135.92.198:10502,TCP;APN:Etisalat,,,

EXT:12.72V,BAT:3.94V;B03:10,0,0,ACC OFF,Stop

862273048221154 is device IMEI

194.135.92.198 is server IP

10502 is port

TCP: TCP or UDP GPRS link protocol

APN:Etisalat,,,: APN, APN name, APN password

EXT:12.72V: External power voltage

BAT:3.94V: Built-in battery voltage

B03:10,0,0: time interval in ACC ON/OFF

ACC OFF: Current ACC state ACC ON/OFF

Stop: Current Move/Stop state

According to the SMS reply you can know if the parameters are wrong and if the power supply is ok.

About the APN, if you know the SIM card operator, you can Google out their APN.

Normally each operator has own APN.

Most operators only have APN, but part operators have APN, APN name, and APN password.

4. IMEI is not correct in the tracking platform

For the new installation, the GPS tracker device is the first time to add to the platform. Some users fill the wrong IMEI number in the platform carelessly. Everything looks ok but the device can't be online.

Double check the IMEI is our suggestion.

For very few devices, they may face the IMEI short or missing due to unclear reason. Just pay attention to that possibility.

5. Device in blind zone

We define "blind zone" as that zone no GSM network signal or too poor GSM network signal. The deivce is failed to send the data out. After the GSM signal recovered, the device will send the stored data automatically.

Asking below questions will help you identify this reason:

a. Does the vehicle keep moving?

b. How long this device was offline?

c. Can reply SMS command or not, how about the respons to calling.

If the vehicle keeps moving, offline for several days, SMS and calling are valid, it is low possibility from the blind zone reason.

But if the vehicle is parking, just oflfine for severa hours, the SMS and calling no respons, suggest you observe longer, it is possible this device is in blind zone.

6. GSM module can't read SIM card

This is the GPS tracker device itself physical problem: GSM module is failed to read the SIM card. The device offline, can't reply the SMS command; If you call the device, normally get remind that the service is off or not available. The orange GSM LED light keeps fast flashing at 0.1 second interval.

If using the debuging software to check the device log data, you will find several consecutive "+CME ERROR: 10" data and the device restarts circularly.

How to know if the GPS tracker device has GSM module problem?

- This is NOT one of the main reasons of offline, happened very few. According to our long-term observation, the rate is less than 0.5% after 12 months using, less than 5% after 5 years using. The users need remove other doubt points first.

- A simple way is the SIM card comparison testing. Insert one proved SIM card which works well in other GPS tracker device, if the offline device still can't work well with the proved SIM card, and the GSM LED light flashes fast, you need doubt the GSM module problem reason.

- Please pay attention to below two factors:

a: Make sure the power supply is normal. If the power supply is not enough (external power or internal battery voltage/electric current too low) the GSM module can't work well.

b: SIM card comparison testing is very important. The GSM module problem and the SIM card itself reason (out of balance, SIM card broken, SIM card without registration, etc) cause same device behaviors such as offline, SMS and calling failure, fast GSM LED light flash, even the debugging software log data is same.

Any GSM module problem conclusion must be based on proved working well SIM card comparison test.