# MC7455 GPS not functioning **URL:** \ **Category:** MC/EM Series\ **Created:** [September 12, 2017, 12:06pm UTC](https://forum.sierrawireless.com/t/mc7455-gps-not-functioning/9484 "2017-09-12T12:06:04Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![evk1206](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/evk1206/32/3772_2.png) [@evk1206](https://forum.sierrawireless.com/u/evk1206)\ **Post date:** [September 12, 2017, 12:06pm UTC](https://forum.sierrawireless.com/t/mc7455-gps-not-functioning/9484/1 "2017-09-12T12:06:04Z")
Hi, Currently I am trying to get GPS messages (NMEA) through MC7455 module. After powering up the module I have three ttyUSB interfaces. If I understood correctly , ttyUSB0 --\> is for diagnostic functionalities ttyUSB1 --\> is for GPS ttyUSB2 --\> is for sending AT commands. I tried seeing the output of /dev/ttyUSB1 through minicom, I didn’t see any NMEA messages. So,I tried to configure the GPS through AT commands I used the following commands: AT!ENTERCND=“A710” OK at!custom? !CUSTOM: GPSENABLE 0x01 GPSLPM 0x01 IPV6ENABLE 0x01 SIMLPM 0x01 USBSERIALENABLE 0x01 SINGLEAPNSWITCH 0x01 OK at!gpstrack? ERROR at!gpstrack=1,255,1000,30,1 ErrCode = 15 OK After running the at command gpstrack I am getting the error code:15 which means error in fix. What should I do to get the NMEA messages. Thanks & regards, vinothkumar ---
**Author:** ![zainol69](https://avatars.discourse-cdn.com/v4/letter/z/c77e96/32.png) [@zainol69](https://forum.sierrawireless.com/u/zainol69)\ **Post date:** [September 12, 2017, 3:17pm UTC](https://forum.sierrawireless.com/t/mc7455-gps-not-functioning/9484/2 "2017-09-12T15:17:00Z")
Hello, I’ve EM7455 installed on DELL Latitude E7270 running dual boot (Ubuntu 17.04 and Windows 10 PRO 64 bit). I’ve tested your commands through Windows 10 via HyperTerm and found out no errors with "AT!GPSTRACK=1,255,1000,30,1 as below: ati Manufacturer: Sierra Wireless, Incorporated Model: EM7455 Revision: SWI9X30C\_02.24.03.00 r6978 CARMD-EV-FRMWR2 2017/03/02 13:36:45 MEID: 35432407003509 IMEI: 354324070035098 IMEI SV: 9 FSN: LF618304770110 +GCAP: +CGSM at!gpstrack=? !GPSTRACK: ,,,, : 1-Standalone, 2-MS-Based, 3-MS-Assisted : 1-255 seconds : 1-4294967280 meters : 1-1000,1000=continuous : 1-65535 seconds OK at!gpstrack=1,255,1000,30,1 OK at!gpsstatus? Current time: 1980 01 06 6 00:32:01 1980 01 06 6 00:00:00 Last Fix Status = FAIL, FAILCODE = 0 1980 01 06 6 00:31:49 Fix Session Status = ACTIVE No TTFF available OK at!gpsstatus? Current time: 2017 09 12 1 15:06:47 2017 09 12 1 15:06:46 Last Fix Status = SUCCESS 2017 09 12 1 15:06:46 Fix Session Status = ACTIVE Which current firmware level of your MC7455 ? Believe your MC7455 should be flashed with latest firmware. ---
**Author:** ![evk1206](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/evk1206/32/3772_2.png) [@evk1206](https://forum.sierrawireless.com/u/evk1206)\ **Post date:** [September 12, 2017, 3:28pm UTC](https://forum.sierrawireless.com/t/mc7455-gps-not-functioning/9484/3 "2017-09-12T15:28:28Z")
Hi, I also have flashed the same firmware to my system. AT+GMR SWI9X30C\_02.24.03.00 r6978 CARMD-EV-FRMWR2 2017/03/02 13:36:45 But still I am getting the same error. at!custom? !CUSTOM: GPSENABLE 0x01 GPSLPM 0x01 IPV6ENABLE 0x01 SIMLPM 0x01 USBSERIALENABLE 0x01 SINGLEAPNSWITCH 0x01 at!gpstrack=1,255,1000,30,1 ErrCode = 15 OK at!gpsstatus? Current time: 1980 01 06 6 00:02:23 1980 01 06 6 00:02:23 Last Fix Status = NONE 1980 01 06 6 00:02:23 Fix Session Status = NONE No TTFF available OK at!gpsstatus? Current time: 1980 01 06 6 00:02:33 1980 01 06 6 00:02:33 Last Fix Status = NONE 1980 01 06 6 00:02:33 Fix Session Status = NONE No TTFF available OK at!gpstrack=1,255,1000,30,1 ErrCode = 15 OK Thanks & regards, Vinothkumar ---
**Author:** ![zainol69](https://avatars.discourse-cdn.com/v4/letter/z/c77e96/32.png) [@zainol69](https://forum.sierrawireless.com/u/zainol69)\ **Post date:** [September 13, 2017, 12:36am UTC](https://forum.sierrawireless.com/t/mc7455-gps-not-functioning/9484/4 "2017-09-13T00:36:59Z")
Hello, If not mistaken, if you would like to access that MC7455 on Linux/Ubuntu via minicom should be through “/etc/ttyUSB2” and make sure “modemmanager” is stopped. Could you try again. ---
**Author:** ![zainol69](https://avatars.discourse-cdn.com/v4/letter/z/c77e96/32.png) [@zainol69](https://forum.sierrawireless.com/u/zainol69)\ **Post date:** [September 13, 2017, 1:08am UTC](https://forum.sierrawireless.com/t/mc7455-gps-not-functioning/9484/5 "2017-09-13T01:08:56Z")
Hello, I’ve MC7455 module installed on DELL E7240 running Ubuntu 17.04 and finished all required Sierra QMI drivers. I’ve tested as you’ve been done where result as below: Welcome to minicom 2.7 OPTIONS: I18n Compiled on Feb 7 2016, 13:37:27. Port /dev/ttyUSB2, 17:00:14 Press CTRL-A Z for help on special keys Manufacturer: Sierra Wireless, Incorporated Model: MC7455 Revision: SWI9X30C\_02.24.03.00 r6978 CARMD-EV-FRMWR2 2017/03/02 13:36:45 MEID: 35907206052419 IMEI: 359072060524192 IMEI SV: 9 FSN: LQ652445790310 +GCAP: +CGSM OK atz OK at!entercnd=“A710” OK at!gpstrack=1,255,1000,30,1 OK at!gpsstatus? Current time: 1980 01 06 6 00:05:28 1980 01 06 6 00:05:28 Last Fix Status = NONE 1980 01 06 6 00:05:14 Fix Session Status = ACTIVE No TTFF available OK at!gpsstatus? Current time: 1980 01 06 6 00:05:36 1980 01 06 6 00:05:36 Last Fix Status = NONE 1980 01 06 6 00:05:14 Fix Session Status = ACTIVE No TTFF available OK Believe our “expert” members could give another input. ---
**Author:** ![alove](https://avatars.discourse-cdn.com/v4/letter/a/57b2e6/32.png) [@alove](https://forum.sierrawireless.com/u/alove)\ **Post date:** [September 13, 2017, 2:46am UTC](https://forum.sierrawireless.com/t/mc7455-gps-not-functioning/9484/6 "2017-09-13T02:46:05Z")
Set GPSLPM = 0 Otherwise, unless you have an active connection, the GPS will go into LPM “GPSLPM”—Enable/disable GPS in Low Power Mode. : • 0 = Enable—GPS engine remains enabled when modem enters LPM (Default) • 1 = Disable—GPS engine is disabled when modem enters LPM ---
**Author:** ![evk1206](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/evk1206/32/3772_2.png) [@evk1206](https://forum.sierrawireless.com/u/evk1206)\ **Post date:** [September 13, 2017, 6:55am UTC](https://forum.sierrawireless.com/t/mc7455-gps-not-functioning/9484/7 "2017-09-13T06:55:03Z")
Hi, Ya. Thank you after seting low power mode active it worked. AT!CUSTOM=“GPSENABLE”,1 AT!CUSTOM=“GPSLPM”,0 AT!RESET and to see the NMEA messages on /dev/ttyUSB1 port we need to send the following message: echo $GPS\_START \> /dev/ttyUSB1 Regards, Vinoth ---
**Author:** ![kiltym](https://avatars.discourse-cdn.com/v4/letter/k/e274bd/32.png) [@kiltym](https://forum.sierrawireless.com/u/kiltym)\ **Post date:** [September 13, 2017, 1:54pm UTC](https://forum.sierrawireless.com/t/mc7455-gps-not-functioning/9484/8 "2017-09-13T13:54:50Z")
I just want to add to this the AT Manual (Rev. 3) states “0” (enabled) is the default mode. ```auto “GPSLPM”—Enable/disable GPS in Low Power Mode. : • 0 = Enable—GPS engine remains enabled when modem enters LPM (Default) • 1 = Disable—GPS engine is disabled when modem enters LPM ``` It does not appear to be correct as it seems “1” (disabled) is the default mode. ---
**Author:** ![brian.gonzalez](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/brian.gonzalez/32/4689_2.png) [@brian.gonzalez](https://forum.sierrawireless.com/u/brian.gonzalez)\ **Post date:** [October 25, 2019, 12:09am UTC](https://forum.sierrawireless.com/t/mc7455-gps-not-functioning/9484/9 "2019-10-25T00:09:20Z")
What makes you think 1 is the default, if it says 0 is the default in the manual as you stated?..