TL-MR6400 4G doesn't connect to mobile 4G band

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TL-MR6400 4G doesn't connect to mobile 4G band

This thread has been locked for further replies. You can start a new thread to share your ideas or ask questions.
TL-MR6400 4G doesn't connect to mobile 4G band
TL-MR6400 4G doesn't connect to mobile 4G band
2025-06-26 12:07:52
Model: TL-MR6400  
Hardware Version: V5
Firmware Version: TL-MR6400(EU)v5_1.7.0_0.9.1_[240716-rel67874]_up_boot_All_Release_2024-07-17_17.59.34

Hi,

I bought a TL-MR6400 and doesn't connect to mobile 4G band.

No possibility to set  manual band (error 89534), nor set 4G only (error code 1 - internal error).

I tried all firmware versions available on official website.

I read several threads on forum without solving.

Last ISP file is outdated compared to firmware versione.

Sim is OK and tested on other devices.

 

Router hw version 5.30 - EU

I have 5 TL-MR6400 , two with hardware V.1 and three with 5.0 : with these no problems, but with the last one (v. 5.3) I can't get connection.

 

System log:

1 2025-06-26 13:58:20 4G Information ERROR: QMI NAS Set preferred network failed, ret = 0.
2 2025-06-26 13:57:31 4G Information ERROR: [band scan] Set pref net failed for pci scan!!!
3 2025-06-26 13:57:31 4G Information ERROR: QMI NAS Set preferred network failed, ret = 0.
4 2025-06-26 13:57:17 SYSTEM Information

User(Mac:00:1D:72:EA:14:11;IP:192.168.1.2) logs in.

 

 

 

 

 

In menu advanced\network\internet after checking sim, the status is disconnected

In advanced\status the network type is "no service"

 

How can I solve ?

 

thank you

 

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#1
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9 Reply
Re:TL-MR6400 4G doesn't connect to mobile 4G band
2025-06-27 07:32:54

Hi@CLA-ATR,

Welcome to our community.

 

For your issue, would you mind trying different SIM cards for this new router? 

Also, you can try the following FAQ troubleshooting suggestions:
No internet connection when using TP-Link Wireless 4G LTE Router working as 3G/4G Router Mode

 

If you don't mind, please take some screenshots of the Advanced page, we can check the status of router to locate the issue.

 

 

 

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#2
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Re:TL-MR6400 4G doesn't connect to mobile 4G band
2025-06-27 08:47:24

  @Joseph-TP 

Hi Joseph, thank you.ù

I already tried different Sims and I already seen and checjed the FAQ link you posted.

I'm out of office for some days, when I'll come back I'send you screenshots.

As said, I have other five MR6400 with the some SIms and network carrier and in that case no problems.

 

Claudio

 

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#3
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Re:TL-MR6400 4G doesn't connect to mobile 4G band
2025-06-27 08:54:46

Thanks@CLA-ATR, Please take your time. 

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#4
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Re:TL-MR6400 4G doesn't connect to mobile 4G band
2025-07-03 06:34:21

  @Joseph-TP Hi, here are the screenshots :

 

 

 

 

 

 

 

 

 

 

if SET “4g only”

 

 

 

 

 

 

IF SET “MANUAL BAND”

 

 

 

 

IF NETWORK SEARCH MANUAL

 

 

 

 

 

 

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#5
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Re:TL-MR6400 4G doesn't connect to mobile 4G band
2025-07-03 06:42:56 - last edited 2025-07-03 06:43:32

COMPLETE DEBUG LOG AFTER CLEANING LOGS AND REBOOT

 

 

 

 

 

 

 

 

 

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#6
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Re:TL-MR6400 4G doesn't connect to mobile 4G band
2025-07-03 06:43:48 - last edited 2025-07-03 06:44:40

 

.

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#7
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Re:TL-MR6400 4G doesn't connect to mobile 4G band
2025-07-04 01:44:02

Hi@CLA-ATR,

Thank you for getting back to me.

 

Please hard reset the TL-MR6400:

Press and hold WPS/RESET button until the Power LED starts flashing to reset the router to its factory default settings

 

Have you created a new profile for a try? Please set the APN Type to Dynamic.

Then go to change to the new profile at the Profile Name option.

 

If it still doesn't work, contact your retailer for a replacement.

 


 

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#8
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Re:TL-MR6400 4G doesn't connect to mobile 4G band
2025-07-10 08:52:59

  @Joseph-TP 

No luck.

I tried with "dynamic APN" but It doesn't work

I'll ask for replacement

 

thank You

Claudio

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#9
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Re:TL-MR6400 4G doesn't connect to mobile 4G band
2025-07-11 02:57:16

Thanks@CLA-ATR ,

Please feel free to contact us if you have any update.

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#10
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