RG255C-GL 5G connection issue

Technical Subjects
1

I’m unable to connect my modem to 5G — it only connects to LTE.
I’ve tried several SIM cards from different countries and tested the modem in various locations around the world, but I’ve never been able to establish a 5G connection. I’m currently in Italy and I would like to try with Italian operators.

I’m using the RG255C-GL module on a Linux board with the ECM driver.
Below are some responses from the AT commands.



AT+QGMR
RG255CGLABR01A04M4G_A0.300.A0.300

OK

AT+COPS?
+COPS: 0,0,"ILIAD",7

OK

AT+C5GREG?
+C5GREG: 0,0

OK

AT+QENG="servingcell"
+QENG: "servingcell","NOCONN","LTE","FDD",222,50,F4F263E,130,2900,7,3,3,D83F,-101,-16,-66,15,0,-,25

OK

AT+QNWPREFCFG="mode_pref"
+QNWPREFCFG: "mode_pref",AUTO

OK

AT+QNWPREFCFG="ue_capability_band"
+QNWPREFCFG: "lte_band",1:2:3:4:5:7:8:12:13:14:17:18:19:20:25:26:28:30:34:38:39:40:41:42:43:48:66:70:71
+QNWPREFCFG: "nr5g_band",1:2:3:5:7:8:12:13:14:18:20:25:26:28:30:38:40:41:48:66:70:71:77:78:79

OK

AT+QMBNCFG="list"
+QMBNCFG: "List",0,1,1,"ROW_Commercial",0x0A01080A,202505121
+QMBNCFG: "List",1,0,0,"FirstNet",0x0A015300,202502271
+QMBNCFG: "List",2,0,0,"Dish_US_Commercial",0x0A015900,202307141
+QMBNCFG: "List",3,0,0,"Commercial-USCC",0x0A011803,202307141
+QMBNCFG: "List",4,0,0,"Rogers_Canada",0x0A014800,202307141
+QMBNCFG: "List",5,0,0,"Telus_Canada",0x0A014900,202307141
+QMBNCFG: "List",6,0,0,"Commercial-Sprint",0x0A010204,202307141
+QMBNCFG: "List",7,0,0,"Commercial-TMO",0x0A010510,202412161
+QMBNCFG: "List",8,0,0,"VoLTE-ATT",0x0A010335,202502271
+QMBNCFG: "List",9,0,0,"CDMAless_Private-Verizon",0x0A01FD28,202503261
+QMBNCFG: "List",10,0,0,"CDMAless-Verizon",0x0A010126,202505141
+QMBNCFG: "List",11,0,0,"STC_SA_Commercial",0x0A014A00,202307141
+QMBNCFG: "List",12,0,0,"Commercial-LGU",0x0A012608,202307141
+QMBNCFG: "List",13,0,0,"Commercial-KT",0x0A01280B,202307141
+QMBNCFG: "List",14,0,0,"Commercial-SKT",0x0A01270A,202307141
+QMBNCFG: "List",15,0,0,"Swiss-Comm",0x0A010411,202307141
+QMBNCFG: "List",16,0,0,"TEF_Spain_Commercial",0x0A010C00,202307141
+QMBNCFG: "List",17,0,0,"TEF_Germany_Commercial",0x0A010CC0,202307141
+QMBNCFG: "List",18,0,0,"Commercial-DT-VOLTE",0x0A011F1F,202307141
+QMBNCFG: "List",19,0,0,"Optus_Australia_Commercial",0x0A014400,202307141
+QMBNCFG: "List",20,0,0,"Telstra_Australia_Commercial",0x0A010F00,202404251
+QMBNCFG: "List",21,0,0,"Commercial-Reliance",0x0A011B0C,202307141
+QMBNCFG: "List",22,0,0,"Commercial-SBM",0x0A011C0B,202307141
+QMBNCFG: "List",23,0,0,"Commercial-KDDI",0x0A010709,202307141
+QMBNCFG: "List",24,0,0,"Commercial-DCM",0x0A010D0D,202307141
+QMBNCFG: "List",25,0,0,"VoLTE-CU",0x0A011561,202404251
+QMBNCFG: "List",26,0,0,"VoLTE_OPNMKT_CT",0x0A0113E0,202404251
+QMBNCFG: "List",27,0,0,"Volte_OpenMkt-Commercial-CMCC",0x0A012010,202410171

OK

Can you tell me what I’m doing wrong or what I could try?

2

Please lock the search priority by “AT + QNWPREFCFG = ‘mode_pref’” and then try again.

3

if you mean this:

AT+QNWPREFCFG=“mode_pref”,NR5G

Yes, I’ve already tried that, and the modem no longer connects in any way and I have to switch back to AUTO to get LTE.

4

Please replace with another uSIM card and try again.

5

I just tested a physical WINDTRE sim(I’m not sure if SA is already activated).
I don’t have a connection.

Here are the AT commands I tried:

AT+COPS?
+COPS: 2

OK
AT+QENG=“servingcell”
+QENG: “servingcell”,“LIMSRV”,“NR5G-SA”,“TDD”,222,88,10D5400F2,673,3A86,517210,2

OK