# Can't set WP7504 to LTE mode on mangOH

**URL:** <https://forum.legato.io/t/cant-set-wp7504-to-lte-mode-on-mangoh/2305>\
**Category:** Uncategorized\
**Created:** [January 3, 2017, 5:53am UTC](https://forum.legato.io/t/cant-set-wp7504-to-lte-mode-on-mangoh/2305 "2017-01-03T05:53:33Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![tconant](https://avatars.discourse-cdn.com/v4/letter/t/ac91a4/32.png) [@tconant](https://forum.legato.io/u/tconant)\
**Post date:** [January 3, 2017, 5:53am UTC](https://forum.legato.io/t/cant-set-wp7504-to-lte-mode-on-mangoh/2305/1 "2017-01-03T05:53:33Z")

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Below are the commands and responses when I try to change the rat mode. The SIM is LTE compatible. Any idea why I’m not able to switch modes? My cell phone is reporting a LTE AT&T connection ( different SIM ), although weak. I’m building the yocot/legato source from Legato-Dist-Source-mdm9x15-SWI9X15Y\_07.11.21.00.tar.bz2. Every attempt to change the mode results in “Failed to set rat value”. I’m able to connect to UMTS fine.

root@swi-mdm9x15:~# cm info  
Device: WP7504  
IMEI: 356207070037255  
FSN: P1636500121210  
Firmware: SWI9X15Y\_07.10.04.00 r32393 CARMD-EV-FRMWR1 2016/06/01 20:30:40  
Bootloader: SWI9X15Y\_07.10.04.00 r32393 CARMD-EV-FRMWR1 2016/06/01 20:30:40

root@swi-mdm9x15:~# cm radio  
Current Network Operator: AT&T  
RAT: UMTS network (LE\_MRC\_RAT\_UMTS)  
Status: Registered, home network (LE\_MRC\_REG\_HOME)  
Signal: Good signal strength (3)

root@swi-mdm9x15:~# cm radio rat LTE  
Failed to set rat value

\*Update: Here is the syslog output from when I attempt to switch the radio RAT mode to LTE

Jan 3 18:37:07 swi-mdm9x15 user.err Legato: =ERR= | modemDaemon[517]/swiQmi T=main | swiQmi.c swiQmi\_CheckResponse() 768 | Sending QMI\_NAS\_SET\_SYSTEM\_SELECTION\_PREFERENCE\_REQ\_MSG\_V01 failed: rc=0 (), resp.result=1.[0x01], resp.error=3.[0x03]  
Jan 3 18:37:07 swi-mdm9x15 user.err Legato: =ERR= | modemDaemon[517]/modemDaemon T=main | le\_mrc.c le\_mrc\_SetRatPreferences() 1337 | Unable to set the Radio Access Technology preferences.  
Jan 3 18:37:07 swi-mdm9x15 user.err Legato: =ERR= | cm[1251]/cm T=main | cm\_mrc.c cm\_mrc\_ProcessRadioCommand() 416 | Failed to set rat value

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<div class="post-metadata">

**Author:** ![Jordan.Zhao](https://avatars.discourse-cdn.com/v4/letter/j/bc79bd/32.png) [@Jordan.Zhao](https://forum.legato.io/u/Jordan.Zhao)\
**Post date:** [January 4, 2017, 3:37am UTC](https://forum.legato.io/t/cant-set-wp7504-to-lte-mode-on-mangoh/2305/2 "2017-01-04T03:37:15Z")

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Did you check if the AT&T bands are supported on WP7504?  
WP7504 supports LTE B2, B4, B5, B12, B17, B25 and B26.

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**Author:** ![tconant](https://avatars.discourse-cdn.com/v4/letter/t/ac91a4/32.png) [@tconant](https://forum.legato.io/u/tconant)\
**Post date:** [January 4, 2017, 3:56am UTC](https://forum.legato.io/t/cant-set-wp7504-to-lte-mode-on-mangoh/2305/3 "2017-01-04T03:56:05Z")

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It looks like AT&T uses bands B2, B4, B17 & B30 for LTE.