# Gprs problem **URL:** \ **Category:** Open AT\ **Created:** [August 19, 2008, 8:00am UTC](https://forum.sierrawireless.com/t/gprs-problem/2438 "2008-08-19T08:00:20Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![sergiulungu](https://avatars.discourse-cdn.com/v4/letter/s/ba8739/32.png) [@sergiulungu](https://forum.sierrawireless.com/u/sergiulungu)\ **Post date:** [August 19, 2008, 8:00am UTC](https://forum.sierrawireless.com/t/gprs-problem/2438/1 "2008-08-19T08:00:20Z")
Hi I have a problem with my gprs connection. I send data via http(GPRS) to a server. I connect to GPRS only when i need to make a transmission. The problem is that (this is according to my gsm operator) the sim card at some point (probably when there is a loss/regain of gsm signal) remains stuck in one cell. Meaning that although the device is already somewhere else (in a different cell) the sim card still tries to connect to the old cell were it thinks it is. Because of this the gprs bearer fails to be started and i can’t start gprs. The restart of the application doesn’t solve this problem. The problem is solved only by calling the mobile operator and they reset the sim card. Is there a way to fix these problem? ---
**Author:** ![ianmceachern](https://avatars.discourse-cdn.com/v4/letter/i/9de053/32.png) [@ianmceachern](https://forum.sierrawireless.com/u/ianmceachern)\ **Post date:** [August 22, 2008, 3:31pm UTC](https://forum.sierrawireless.com/t/gprs-problem/2438/2 "2008-08-22T15:31:43Z")
I’ve seen this problem periodically. However, it’s not the mobile that gets stuck its the database on the network side that has the problem. I was told that the network thinks its on one cell, the mobile hears a different cell and thinks its on that tower. Thus things don’t work in either direction. In my case the mobiles were stopped at fixed location for a couple of months when the problem occured. In these cases it always required a power cycle of the device to get do a re-registration. Once in a while they need to do a “flush” at the network side (basically they reset the SIM). You might want to add into your application a CFUN=0 and restart the radio periodically or when the problem occurs. ---
**Author:** ![sergiulungu](https://avatars.discourse-cdn.com/v4/letter/s/ba8739/32.png) [@sergiulungu](https://forum.sierrawireless.com/u/sergiulungu)\ **Post date:** [August 26, 2008, 7:54am UTC](https://forum.sierrawireless.com/t/gprs-problem/2438/3 "2008-08-26T07:54:05Z")
I’ve read the documentation for at+cfun=0 and i’m a little puzzled regarding what it does. What is the difference between at+cfun=0 and at+cfun=1. I mean it say that cfun=0 does an imsi detach and sim cannot be accessed , while at+cfun=1 does a restart of the gsm stack an functionality. Is it safe to say that when a cfun=1 is done it is safer to do a cfun=0 first? > [@](#): > > You might want to add into your application a CFUN=0 and restart the radio periodically or when the problem occurs. I’m doing a cfun=1 everytime a bearer problem appears shouldn’t this be enough or i didn’t grasp exactly what this cfun command does? ---
**Author:** ![sergiulungu](https://avatars.discourse-cdn.com/v4/letter/s/ba8739/32.png) [@sergiulungu](https://forum.sierrawireless.com/u/sergiulungu)\ **Post date:** [September 23, 2008, 11:01am UTC](https://forum.sierrawireless.com/t/gprs-problem/2438/4 "2008-09-23T11:01:51Z")
I am doing cfun=0 when the problem occurs but it doesn’t seem to help solve the problem. Any other suggestion? ---
**Author:** ![awneil](https://avatars.discourse-cdn.com/v4/letter/a/49beb7/32.png) [@awneil](https://forum.sierrawireless.com/u/awneil)\ **Post date:** [September 23, 2008, 12:30pm UTC](https://forum.sierrawireless.com/t/gprs-problem/2438/5 "2008-09-23T12:30:08Z")
AT+CFUN=0 should cause the module to detach in an orderly fashion from the network; AT+CFUN=1 should completely restart the GSM stack - so, if the network still thinks the unit is in another cell, then the problem must lies in the network - as ianmceachern said. You need to speak to your network operator about this - if they know how to fix it, they must know what causes it…? ---
**Author:** ![sergiulungu](https://avatars.discourse-cdn.com/v4/letter/s/ba8739/32.png) [@sergiulungu](https://forum.sierrawireless.com/u/sergiulungu)\ **Post date:** [September 23, 2008, 12:40pm UTC](https://forum.sierrawireless.com/t/gprs-problem/2438/6 "2008-09-23T12:40:36Z")
Well actually i talked to the network operator and they said that this thing just occurs, without any known pattern or cause 🙂 as far as they know. So i was hopping for a solution on my end. ---
**Author:** ![sergiulungu](https://avatars.discourse-cdn.com/v4/letter/s/ba8739/32.png) [@sergiulungu](https://forum.sierrawireless.com/u/sergiulungu)\ **Post date:** [October 6, 2008, 3:17pm UTC](https://forum.sierrawireless.com/t/gprs-problem/2438/7 "2008-10-06T15:17:27Z")
Using EDGE instead of GPRS could solve this problem? Anybody has some experience in this?