Arduino Uno with M5100B-D GSM Shield network connection

Hi All.
I am new to working with Arduinos and prototyping and I am having difficulty with a project I have committed myself to. A bit of background: The project is intended to use my Arduino Uno with an GSM shield to triangulate location at frequent and repeating intervals. So far I have the hardware set up and working to a stage of two way communication between my computer and the shield. Upon activation I receive:

Starting SM5100B Communication…

+SIND: 0

+SIND: 10,“SM”,0,“FD”,0,“LD”,0,“MC”,0,“RC”,0,“ME”,0

+SIND: 8

After doing some research I have established that this means I am not properly connected to the cell tower network (makes sense, since I cannot retrieve information about the network or connected cellids). My attempt at a resolution was to change the frequency on which the shield was recieving by commanding:


This was intended to change the frequency to the correct range, given by my service provider. This has not proven successful and I am reaching out for help to anyone who may be more versed with this stuff. (so far I have been following the guidance prescribed at this blog:

The hardware I have installed are listed below:

  1. Arduino Uno
  2. Spreadtrum communications INC. model number M5100B-D
  3. an attached antenna,
  4. 9V direct AC power supply
  5. Vergin Mobile Sim Card LTE

Thank you for your help!!

  • Jff-M


The connection +Sband: 0 indicates the sim card is not inserted. There is a connection error between my Vergin Mobile Sim card and the shield. Could anyone confirm this issue or a workaround?


I've been having exactly the same problem today. After unplugging the GSM module from the shield and plugging it back in several times it has mysteriously started working. So I'd check the connection between shield and module is clean.

Yea I tripple checked the connection :stuck_out_tongue: but its a good thought and on the right track from my error. After a few more hours and an attempt with a SIM card from a different provider, I found that Virgin Mobile uses CDMA instead of GSM and therefore the SIM card is not recognized by the shield. The Rogers SIM card that I tired worked like a charm.