# Lenovo p50 Em7455 No service error **URL:** \ **Category:** MC/EM Series\ **Created:** [June 24, 2021, 3:24pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085 "2021-06-24T15:24:05Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![behi4321](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@behi4321](https://forum.sierrawireless.com/u/behi4321)\ **Post date:** [June 24, 2021, 3:24pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/1 "2021-06-24T15:24:05Z")
hello i have a P50 lenovo Laptop and EM7455 installed i have this error ![image](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/5/542a264f7a3530e37051c63014312d26df672fdf.png) device manager : ![image](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/3/3609976e9fad5882afd497b1cbde53acb3f9b03d.png) ![image](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/2/27e22aa0f961653e72967104ef6489cea823b844.png) ![image](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/6/6de023dcc31b65567cd3c8098cb0b437c751d698.png) ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/jyijyi/32/4766_2.png) [@jyijyi](https://forum.sierrawireless.com/u/jyijyi)\ **Post date:** [June 25, 2021, 1:08am UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/2 "2021-06-25T01:08:35Z")
you need to enable the modem port for AT command for further investigation: > [@no cellular service for em7455 with window10!](https://forum.sierrawireless.com/t/no-cellular-service-for-em7455-with-window10/9430/17): > > Alright all done Still the same Skylight states radio is turned off[skylight] ---
**Author:** ![behi4321](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@behi4321](https://forum.sierrawireless.com/u/behi4321)\ **Post date:** [September 19, 2021, 1:54pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/3 "2021-09-19T13:54:29Z")
> [@jyijyi](#): > > you need to enable the modem port for AT command for further investigation: Finally after war with covid19 i m changed OS and now i can run AT command šŸ˜… ```auto AT!GSTATUS? !GSTATUS: Current Time: 683Temperature: 43 Reset Counter: 4Mode: ONLINE System mode: WCDMA PS state: Not attached WCDMA band: WCDMA BC3 WCDMA channel: 1294 GMM (PS) state:DEREGISTERED PLMN SEARCH MM (CS) state: IDLE PLMN SEARCH WCDMA L1 state:L1M_ACQ LAC: 0000 (0) RRC state: DISCONNECTED UTRAN Cell ID: 00000000 (0) RxM RSSI C0: --- RxD RSSI C0: --- RxM RSSI C1: --- RxD RSSI C1: --- OK ``` ```auto AT!impref? !IMPREF: preferred fw version: 02.33.03.00 preferred carrier name: GENERIC preferred config name: GENERIC_002.072_000 preferred subpri index: 000 current fw version: 02.33.03.00 current carrier name: GENERIC current config name: GENERIC_002.072_000 current subpri index: 000 OK ``` ```auto Found Applications port COM7 Found Diagnostics port COM6 Found modem : EM7455 IMEI : **** Serial NR. : LF70840 ***** Firmware : SWI9X30C_02.33.03.00 Voice feature : disabled SIM Lock status : unlocked ``` ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/jyijyi/32/4766_2.png) [@jyijyi](https://forum.sierrawireless.com/u/jyijyi)\ **Post date:** [September 19, 2021, 2:44pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/4 "2021-09-19T14:44:19Z")
Why it is not in lte mode? How about at!selrat? ---
**Author:** ![behi4321](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@behi4321](https://forum.sierrawireless.com/u/behi4321)\ **Post date:** [September 19, 2021, 2:45pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/5 "2021-09-19T14:45:23Z")
at!selrat? !SELRAT: 00, Automatic OK ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/jyijyi/32/4766_2.png) [@jyijyi](https://forum.sierrawireless.com/u/jyijyi)\ **Post date:** [September 19, 2021, 2:45pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/6 "2021-09-19T14:45:53Z")
Is your sim card for lte network ---
**Author:** ![behi4321](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@behi4321](https://forum.sierrawireless.com/u/behi4321)\ **Post date:** [September 19, 2021, 2:48pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/7 "2021-09-19T14:48:01Z")
Iā€™m tested 3 kind of sim available in iran MTN sim TD-LTE sim 4G sim in all of them i Have No Service erorr ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/jyijyi/32/4766_2.png) [@jyijyi](https://forum.sierrawireless.com/u/jyijyi)\ **Post date:** [September 19, 2021, 2:49pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/8 "2021-09-19T14:49:14Z")
How about sending at!band? ---
**Author:** ![behi4321](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@behi4321](https://forum.sierrawireless.com/u/behi4321)\ **Post date:** [September 19, 2021, 2:49pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/9 "2021-09-19T14:49:31Z")
at!band=? Index, Name 00, All bands 01, Europe 3G 02, North America 3G 06, Europe 07, North America 08, WCDMA ALL 09, LTE ALL OK ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/jyijyi/32/4766_2.png) [@jyijyi](https://forum.sierrawireless.com/u/jyijyi)\ **Post date:** [September 19, 2021, 2:50pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/10 "2021-09-19T14:50:22Z")
How about sending at!band? ---
**Author:** ![behi4321](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@behi4321](https://forum.sierrawireless.com/u/behi4321)\ **Post date:** [September 19, 2021, 2:51pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/11 "2021-09-19T14:51:06Z")
at!band? Index, Name 00, All bands OK ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/jyijyi/32/4766_2.png) [@jyijyi](https://forum.sierrawireless.com/u/jyijyi)\ **Post date:** [September 19, 2021, 2:52pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/12 "2021-09-19T14:52:21Z")
Did you connect antenna? How about at+csq ---
**Author:** ![behi4321](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@behi4321](https://forum.sierrawireless.com/u/behi4321)\ **Post date:** [September 19, 2021, 2:53pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/13 "2021-09-19T14:53:09Z")
at+csq +csq: 99,99 OK ---
**Author:** ![behi4321](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@behi4321](https://forum.sierrawireless.com/u/behi4321)\ **Post date:** [September 19, 2021, 2:57pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/14 "2021-09-19T14:57:00Z")
no . based on u tube video Iā€™m just inserted the module in slot under the keyboard of Lenovo P50 if Antenna is required i will buy an antenna! ![image](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/d/d9d54e00a5b03eafbb84250af63424d6c15b5041.jpeg) i can use wlan antenna for em7455? ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/jyijyi/32/4766_2.png) [@jyijyi](https://forum.sierrawireless.com/u/jyijyi)\ **Post date:** [September 19, 2021, 3:22pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/15 "2021-09-19T15:22:05Z")
Seems there is no signal received ---
**Author:** ![behi4321](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@behi4321](https://forum.sierrawireless.com/u/behi4321)\ **Post date:** [September 19, 2021, 3:42pm UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/16 "2021-09-19T15:42:08Z")
> [@behi4321](#): > > i can use wlan antenna for em7455? No service means No Signal ? i will buy an antenna! šŸ¤’ ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/jyijyi/32/4766_2.png) [@jyijyi](https://forum.sierrawireless.com/u/jyijyi)\ **Post date:** [September 20, 2021, 1:14am UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/17 "2021-09-20T01:14:59Z")
if it registers network, +CSQ should return some value: ```auto ati3 Manufacturer: Sierra Wireless, Incorporated Model: MC7430 Revision: SWI9X30C_02.36.00.00 r8395 CARMD-EV-FRMWR2 2020/10/28 06:33:51 MEID: 35907406009754 IMEI: 359074060097542 IMEI SV: 22 FSN: LU626300170410 +GCAP: +CGSM OK at!gstatus? !GSTATUS: Current Time: 1603066 Temperature: 30 Reset Counter: 1 Mode: ONLINE System mode: LTE PS state: Attached LTE band: B7 LTE bw: 20 MHz LTE Rx chan: 3150 LTE Tx chan: 19385 LTE CA state: NOT ASSIGNED EMM state: Registered Normal Service RRC state: RRC Idle IMS reg state: No Srv PCC RxM RSSI: -67 RSRP (dBm): -93 PCC RxD RSSI: -95 RSRP (dBm): -126 Tx Power: -- TAC: 0462 (1122) RSRQ (dB): -5.5 Cell ID: 04A5410D (77938957) SINR (dB): 25.4 OK at+csq +csq: 23,99 OK ``` ---
**Author:** ![behi4321](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@behi4321](https://forum.sierrawireless.com/u/behi4321)\ **Post date:** [September 20, 2021, 6:57am UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/18 "2021-09-20T06:57:21Z")
i m connected en external antenna from another Lenovo laptop and its is worked for few minute (antenna percentage 20%) šŸ¤© but after restart module is turned off and cant be turned on ```auto !GSTATUS: Current Time: 1057Temperature: 40 Reset Counter: 2Mode: LOW POWER MODE OK ``` How to diable Low Power Mode ? ```auto at!pcinfo? State: Low Power Mode LPM voters - Temp:0, Volt:0, User:0, W_DISABLE:1, IMSWITCH:0, BIOS:0, LWM2M:0, OMADM:0, FOTA:0 LPM persistence - None OK ``` ```auto AT+CFUN? +CFUN: 0 OK ``` edited ---
**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/jyijyi/32/4766_2.png) [@jyijyi](https://forum.sierrawireless.com/u/jyijyi)\ **Post date:** [September 20, 2021, 7:12am UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/19 "2021-09-20T07:12:44Z")
what is the response of AT+CFUN? ---
**Author:** ![behi4321](https://avatars.discourse-cdn.com/v4/letter/b/57b2e6/32.png) [@behi4321](https://forum.sierrawireless.com/u/behi4321)\ **Post date:** [September 20, 2021, 7:16am UTC](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085/20 "2021-09-20T07:16:50Z")
ss ```auto AT+CFUN? +CFUN: 0 OK ``` [Next page](https://forum.sierrawireless.com/t/lenovo-p50-em7455-no-service-error/24085.md?page=2)