GM862-GPS not registering to network

GPS/GNSS Development Boards
1

Hi,

I bought a GM862 Evaluation Kit - USB last week, and got it delivered just two days ago. I was really excited about it, but I have had the same problem since the first time I turned it on…

Drivers were installed properly and the module works “fine” it just can’t register to any network in my country (Mexico), I have tried 3 different sim cards already from two different companies (TELCEL & MOVISTAR) and the result is the same:

AT+CREG?

+CREG: 0,2

I have tried all bands (0,1,2,3) and nothing, the thing is dead!!

I even upgraded the firmware to 7.02.404 via Round Solutions downloads.

I am beginning to think the module might be broken or something.

Does anybody have any suggestions?

I have followed the software user guide completely. The module works fine, it talks to me and everything, but it just does NOT register to any network, which makes it pretty useless!!

I have tried switching DTR switch LOW and HIGH, but nothing.

Please gimme some help, PLEASE!! :frowning:

2

Never had any issues like this.

What does AT+CPIN? return?

3

I know it’s strange, I am running out of ideas.

CPIN tells me the SIMs are good.

AT+PIN?

+CPIN: READY

THis happens with all the SIMS I insert which is ok I guess, those SIMS actually work on real cellphones.

Yesterday I talked to one of my professors in University and he told me he believes it’s the the carrierst that are giving me a hard time. He suggested I went to one CSO and talked to someone explaing my project and my PROBLEM! So I did it, I talked to this guy who lent me one virgin SIM, it doesn’t even have a phone number registered to it, and he also lent me his own personal SIM from the company. I know this company (MOVISTAR) works on BND=3 so I set this up, and inserted the virgin SIM.

Beautiful, after running AT+CREG? a couple of times it threw +CREG: 0,3

I thought this should be ok, at least it can see the carrier. I ran AT+COPS=? and AT#MONI and they both worked. Then I inserted this guy’s SIM and there it was +CREG 0,1 Awesome I thought, I started playing with it right there in his office and tried to call a number but after dialing the module threw Error, no carrier, I tried it twice and the same thing happened.

I asked him what could be the reason, and he told me that SIM was open to any call and everything was free for him, because it was a SIM from the company. He told me, the servers might be blocking autgoing calls when detecting the SIM was not inserted in the original phone.

I dont know, this doesn’t make a lot of sense to me, but I really dont know a lot about carriers politics.

He suggested that I bought a SIM with a phone number that wasn’t matched to any cellphone for about $10, I’ll do this tomorrow.

He gave me the virgin sim and when I got home I tried it again here, but now it only throws

AT+CREG?

+CREG: 0,2

It can not connect. I know what you are probably thinking, there’s no reception here, but that’s not the case, my real cellphone works flawlessly here, 4 bars and everything.

I am beginning to think about warranty here!!!

HELP guys please!! This is my dream… and also my senior year project!!

:stuck_out_tongue:

4

i see true problems and also i should add that in BND=3, module crashes and i can do nothing, pls any :idea:

5

Hi ,

I had similar problem and sadly I discovered that this was related with the power supply since the module when working with GSM “needs” more power.

Carlos