SIM900 cannot register to network.

Hi,

I'm using a SIM900 module within Australia, Sydney. I'm currently using a Vodafone sim, according to this website, https://www.accesscomms.com.au/reference/mobnet.htm, the 900MHz 2G band is supported within Australia.

My device is connected with a power supply that can output max 3A. I have also included the schematics that were sent to me upon purchase.
My problem is that once I power on the device the NETLIGHT LED blinks at a 800ms off 64ms on, singalling SIM900 does not find the network.

I have trouble shooted with the following commands



From this, I believe that the antenna is not the issue in all of this.

following this I tested the sim card


I think this means that communications to the sim are okay?

Next I tested the engineering mode


This is the part that struck me as particularly odd, In the mobild country code for +CENG:0 , there is the number 1665, when in actual fact I would be expecting 505 for Australia?

finally testing ,


Tommorrow I plan on obtaining another simcard that works on the Telstra network and test if it registers to the network. But overall, I'm unsure of why the module is not connecting to the Vodafone AU network. Has anyone had this kind of experience before?

Regards,
Luke.

hi! problem like this do occur with some GSM modem. However, visiting the telecom company or calling their customer care hotline might be a solution. That is to know if the device can be use on their network. or try the other way out by using another simcard from another network. Goodluck.

Hi,

I talked to an engineer that works at the telecom company and they didn't know why it would be happening.

As I said I would, I purchased two different sims that work on both Optus and Telstra respectively. I received the following response


more interesting this time was when I typed the command AT+CPIN? and got the response


My understanding is that PH-NET PIN is Network personnalisation is required. I'm unsure of why I'm getting this for the command. This occurs for the both Telstra and Optus simcard. But not the Vodafone simcard. Is there any insight as to why this may be happening? Any other commands I can try?

regards,
Luke.

Hello!
Are you having the correct version of your modem manual? Then read on "AT+COPS Operator selection".
With this I hope it will be of major guide.
Note: modem version is always a thing to take note of in term of command and syntax the can interpret.

I have read the AT commands section thoroughly for the sim900, you'll notice that it selects the network that it is meant to connect to as 'Current' when using the command AT+COPS=?

Reset the modem to the factory default using AT command, and if the registration is still required......
then try the steps below

SET THE MODULE TO AUTO REPORT STATUS INFO ON POWER UP
AT COMMAND FUNCTION
AT+IPR=115200 The baud rate must be set; does not work on Auto Baud
AT+CREG=1 Set the Module to report on network registration query
<POWER OFF AND POWER UP AGAIN>
RDY Indicates power key was pressed
+CFUN: 1 Module is on full functionality
+CIPN: READY Indicates no pin number required, “SIM PIN” will display if pin number is needed
+CREG: 0 Not registered on the network
+CREG: 2 Searching for a network to register to
Call Ready Ready for Voice and SMS
+CREG: 1 Registered on network

SET MODULE TO AUTO REPORT STATUS AND NETWORK INFO ON POWER UP
AT COMMAND FUNCTION
AT+IPR=115200 The baud rate must be set; does not work on Auto Baud
AT+CREG=2 Set the Module to report on status and network registration query
<POWER OFF AND POWER UP AGAIN>
RDY Indicates power key was pressed
+CFUN: 1 Module is on full functionality
+CIPN: READY Indicates no pin number required, “SIM PIN” will display if pin number is needed
+CREG: 0 Not registered on the network
+CREG: 2 Searching for a network to register to
Call Ready Ready for Voice and SMS
+CREG: 1,”009A”,”2C30” Registered on network, showing cell ID and Location ID

Hi Folks!

Any solution for this please? I have the very same problem in Hungary..
CSQ: 23,0
CREG: 1,0 ( after reset or powering on it changes to CREG:1,2 then back to CREG:1,0... module is not searching a new operator)
COPS (2,"T-Mobile.....) - it can see the operator, and shows T-Mobile as current one ..
however CREG: 1,0 ....AT+COPS? COPS:0

The netlight blinks with 800ms.. no network..

If I try to get it registered manually I get an error message:
AT+COPS=0,2,"21630" - CME error: operation not allowed


I've tried 3 different sim cards/two operators, but did not help.

Hi Hunkar I encountered the same problem but after updating the SIMCOM firmware the modem works fine now.

Hello !

Do you remember witch version you have had ? and what is the new version ?
I've buy a SIM900 modul on eBay and it's the same problem like evryone here :roll:

gkiwango said:

Hi Hunkar I encountered the same problem but after updating the SIMCOM firmware the modem works fine now.

Click to expand...

I have this very problem, I would like also to try to update the firmware. Where did you get the firmware, please?

Hi All!

You can easily update the firmware of you SIM900A Module.

First of All, you have to get the version of your current firmware, you can get it with "AT+CGMR" AT command, after that you have to download the equivalent SIM900 firmware from **broken link removed**

(Check if your module has 32 or 64 bit frimware)


After you dowloaded the link, you can flash it to you module ( Be care of the voltage levels)

I found a "step by step" tutorial to flash your module, and it works well.
Here is this tutorial http://www.geekonfire.com/wiki/index.php?title=GPRS_Shield%EF%BC%88SIM900%EF%BC%89_Firmware_Update

Good Luck! ;-)

Regards,

Ben