Hello people!!, i want to send and recieve messages from my q2686 with a test board. Qhen i run Telemetry.c i cant make a registration ( +CREG=0,2). But the strage thing is that the SIM card works fine in a cell phone, and the signal level is aparently OK (+CSQ= 12,0). Can anyone gove me a hand?.
Than you for advance.
Do you have the correct frequency band(s) selected?
Hiya,
Do you have a good antenna? Is the module making a good connection with the dev board? You really should solder at least one of the ground pins on the Q2686 module to the dev board - the pin closest to the antenna connection is a good one.
ciao, Dave
If it’s on a custom board, check very carefully with an oscilloscope that the power supply is absolutely solid!
See: viewtopic.php?f=29&t=3152&p=11704&hilit=oscilloscope#p11704
As the unit starts up, the point where it tries to GSM register is the first time that it really draws its full current - so, if you have a power supply problem, that is likely to be the point at which it will show-up.
If the power supply “dips” - even momentarily - while the unit is transmitting, that is very liekly to cause the registration to fail.
Its working!!! 
. It was a hardware problem!!!. Thank you so much for the replies. I can send sms with the AT comands and make a GPRS client too!!. If anyone needs the code please send me a personal message or a email.
Thanks again!!!.
It seems that the power supply wasnt rith enough. I must have as nominal 3.6V and i was having 3.1V.