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SIM900 GPRS Module no Sim_VDD

Posted: Wed Apr 10, 2013 6:45 pm
by joe540
Hi!

I've bought 2 SIM900 Arduino GPRS Shield and have the same problem : After power up, i got this message from SIM900 Uart

Code: Select all

RDY

+CPIN: NOT INSERTED

+CFUN: 1
As far as i know, CPIN: Not Inserted mean that it does not detect de SIM Card. I probed the Sim_VDD Pin with a voltmeter an got no voltage. I tried ton push on the sim card, to clean it, but it do the same with my two shields. The shield is actually powered by a 5V 3A External power supply. The regulator works fine, i've got a 3V output on the Backup battery header so it's not power related.

Is there a config that must be done on the SIM900 to provide the SIM_VDD power?

I tried with the stock Firmware (1137B03SIM900M64_ST_MMS) and tried to upgrade to version B08(1137B08SIM900M64_ST) and B11 (1137B11SIM900M64_ST_TCP_SERVER) without success. Please help!

Re: SIM900 GPRS Module no Sim_VDD

Posted: Thu Apr 11, 2013 9:45 am
by techsupport
Hi,friend
Maybe you didn't observe the SIM900 GPRS shield carefully, there is a power select nearby the Power jack. The power select selects the power supply for GPRS shield(external power or 5v of arduino), and the Power jack connecte to external 4.8~5VDC power supply.

It's good for you, http://www.geeetech.com/wiki/index.php/ ... PRS_Shield

Re: SIM900 GPRS Module no Sim_VDD

Posted: Fri Nov 18, 2016 3:15 am
by Laimonas
O have the same issue.

checked all as givin in date sheet, checked SIM card (working fine) placed 3v battery in as well. but stil the sim is not been read.

+CFUN: 1

+CPIN: NOT INSERTED

PLEASE HELP!!!!

Re: SIM900 GPRS Module no Sim_VDD

Posted: Fri Nov 18, 2016 7:26 pm
by Laimonas
I have change a provider (to vodafone) the privios network provider doesnt support GSM.

it has sorted mine issue was able to send text