Quectel RM502Q-AE Only connects at 4G, not getting 5G bands

Hello, I have the Quectel RM502Q-AE, It works very well but only on 4G bands, I cannot get modem to connect to 5G ever, I’ve driven up next to 2 seperate Cell Towers that are broadcasting 5G (phone says 5Guc) but this modem only connects at 4G bands, testing with two different sim (AT&T and T-mobile) and modem will only register various 4G bands only. I have gone through various AT commands listed in the pdf manual but I can never boot up to any 5G nXX bands, only stuck at 4G. Is this a Firmware issue I should maybe downgrade or other AT settings I should be applying? Thank you

All 4 antennas are hooked up and have rechecked connectors. Tried factory reset.

Company name and located city:
BullRunComm
Project name (so we can refer to it in the future):
BullRun5G
Application type:
Internet
Estimated Annual Units (for series production):
1
Project timeline:
1year
Current status:
testing different 5G module manufacturers
From which distributor do you buy Quectel modules & EVB kits?
AliExpress
Do you have EVB kit for this application?
No

Modem Debug:
at+qgmr
RM502QAEAAR11A04M4G_01.002.01.002
+COPS: 0,0,“AT&T”,7
OK
AT+COPS=3,2;+COPS?
+COPS: 0,2,“310410”,7
OK
Sun Jan 9 03:59:04 2022 : /dev/ttyUSB2 AT+CREG=2;+CREG?;+CREG=0
+CREG: 2,1,“1208”,“9F6DE09”,7
OK
AT+CEREG=2;+CEREG?;+CEREG=0
+CEREG: 2,1,“1208”,“9F6DE09”,7
OK
AT+C5GREG=2;+C5GREG?;+C5GREG=0
+C5GREG: 2,0
OK
Sun Jan 9 03:59:09 2022 : /dev/ttyUSB2 AT+CSQ
+CSQ: 20,99
OK
AT+QENG=“servingcell”
+QENG: “servingcell”,“NOCONN”,“LTE”,“FDD”,310,410,9F6DE09,178,850,2,5,5,1208,-103,-15,-66,14,8,210,-
OK
AT+QRSRP
+QRSRP: -103,-140,-140,-136,LTE
OK
AT+QCAINFO
+QCAINFO: “PCC”,850,100,“LTE BAND 2”,1,178,-103,-15,-66,10
OK
AT+QCFG=“nwscanmode”
ERROR
AT+QNWPREFCFG=“mode_pref”
+QNWPREFCFG: “mode_pref”,AUTO
OK
AT+QTEMP
+QTEMP:“qfe_wtr_pa0”,“26”
+QTEMP:“qfe_wtr_pa1”,“0”
+QTEMP:“qfe_wtr_pa2”,“0”
+QTEMP:“qfe_wtr_pa3”,“0”
+QTEMP:“aoss0-usr”,“30”
+QTEMP:“mdm-q6-usr”,“31”
+QTEMP:“ipa-usr”,“31”
+QTEMP:“cpu0-a7-usr”,“31”
+QTEMP:“mdm-5g-usr”,“30”
+QTEMP:“mdm-vpe-usr”,“31”
+QTEMP:“mdm-core-usr”,“31”
+QTEMP:“xo-therm-usr”,“30”
+QTEMP:“sdx-case-therm-usr”,“31”
OK

Sun Jan 9 03:59:21 2022 : /dev/ttyUSB2 AT+CPMS=“SM”
+CPMS: 29,30,29,30,29,30

Thank you!
Piran

Dear Sir,
Thanks for your question. Please also check at+qnwprefcfg=“nr5g_band”/at+qnwprefcfg=“nr5g_disable_mode”/AT+QNWPREFCFG=“rat_acq_order”
image


image
From the at log you tested, the signal is not good, can you show me picture about your device and antennas?
Thanks!

Hello Peter, Thanks for your reply,

I ran your 3 requested commands result:
AT+QNWPREFCFG= “nr5g_band”
AT+QNWPREFCFG: “nr5g_band”,1:2:3:5:7:8:12:20:25:28:38:40:41:48:66:71:77:78:79

OK
::::
AT+QNWPREFCFG=“nr5g_disable_mode”
+QNWPREFCFG: “nr5g_disable_mode”,0

OK
::::
AT+QNWPREFCFG= “rat_acq_order”
+QNWPREFCFG: “rat_order_pref”,NR5G:LTE:WCDMA

OK

AT+QRSRP?
+QRSRP: -105,-120,-140,-140,LTE

OK

i removed this card and put into another housing with four new MFH4’s and still same poor signal results right next to a 5G tower. do the -140 & -140 mean that port 2 and 3 are failing to connect to the antenna, i’ve already replace the wires with new twice.

Dear Sir,
Can you show me picture about your device and antennas, do your antennas support 5G band?

I’ve tried many antenna combinations, best I can get is b41 at 100% signal next to tower, but it never gets 5G.

is their any kind of warranty on this product?

We test each module to ensure the quality before leaving our factory.
From the at log you sent, the signal is very weak, do you have our antennas for comparative test?

Hello Peter! Based on recommendations from Quectel modem users on Facebook groups, It seems I was using 1 year or older 4G SIM cards only. I then went to the store’s (ATT & T-mobile) and was issued new (01/2022) replacement SIM cards that are 5G compatible. I am now beginning to see 5G NR on the connection details.

In the process of testing I had downgraded the modem firmware, could you post here a link for us to where we can download the latest RM502 firmware so that we may update back to new?

Thank you so much for your help Peter!
Piran

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