Need help with new WG3526 - MC7455 | AT&T SIM - Not connecting to LTE

[JamesReinhold]

Hello - I've exhausted the tutorials and troubleshooting guides over the past several days and need some guidance please.

The BLUF is that I can't seem to connect to LTE, I can only connect to WCDMA. In my last attempt - I packed everything in the car and drove "to town" thinking signal was the issue. No change. I've based my coverage assumptions from the map that RootMetrics publishes and there is AT&T LTE coverage in my area (22942).

Equipment: New WG3526 and MC7455 (from The Wireless Haven)
Antennae: Eightwood 2pcs 5dbi 3G 4G LTE Antenna SMA Plug Male Omni- Directional (From Amazon)
Firmware: WIFIX GoldenOrb (openwrt-wg3526-GO2018-09-02-upgrade)
SIM: AT&T PrePaid, purchased through Amazon, activated by NetBuddy.co

I started out with the tutorial WG3526 - Building a MC7455 CAT6 LTE Router and was not successful in connecting. I followed this up with the MC7455 and ROOTer - Troubleshooting Connection Issues and am still no luck. I've combed through the forums and feel like I've tried everything possibly related in the other posts.

One of the things that I've noted is that through all of my attempts - I don't get the impression that the SIM is registering properly with AT&T. I did ask Netbuddy to confirm that they activated it, and they replied that it was - but I wonder, not having any experience with it or any other way to verify the SIM works.

So status where I'm at:
- Performed reset and reprogram of MC7455

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at!entercnd="A710"
AT!RMARESET=1
at!reset

Hard re-boot, Followed by

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at!entercnd="A710"
at!usbcomp=1,1,1009
at!custom="IPV6ENABLE",1
at+cfun=1
at!selrat=06
at+cgdcont=1,"ipv4v6","broadband"
at!reset

Hard re-boot, insert SIM - no dice.

Reset Router Firmware and re-enter APN to "broadband"; still no luck. Here's the info that I've pulled using the various AT commands in hope someone with more experience might be able to point me in the right direction:

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AT!GSTATUS?
!GSTATUS: 
Current Time:  195		Temperature: 37
Reset Counter: 1		Mode:        ONLINE         
System mode:   WCDMA      	PS state:    Not attached 
WCDMA band:    WCDMA 850  
WCDMA channel: 1007
GMM (PS) state:DEREGISTERED   	LIMITED SERVICE
MM (CS) state: IDLE           	NORMAL SERVICE 

WCDMA L1 state:L1M_PCH_SLEEP  	LAC:         2AEC (10988)
RRC state:   DISCONNECTED   	Cell ID:     0B9183BB (194085819)
RxM RSSI C0:   -93		RxD RSSI C0:  --- 
RxM RSSI C1:    --- 		RxD RSSI C1:  --- 


OK

AT+COPS?
+COPS: 0,0,"AT&T",2

OK

AT!LTEINFO
!LTEINFO: 
Not Available


OK

AT+CPIN?
+CPIN: READY

OK

AT+CNUM
OK

at!usbcomp?
Config Index: 1
Config Type:  1 (Generic)
Interface bitmask: 00001009 (diag,modem,mbim) 

OK

at!gobiimpref?
!GOBIIMPREF: 
 preferred fw version:    02.24.05.06
 preferred carrier name:  GENERIC
 preferred config name:   GENERIC_002.026_000
 current fw version:      02.24.05.06
 current carrier name:    GENERIC
 current config name:     GENERIC_002.026_000

OK

Thanks in advance for any assistance.

[JimHelms]

First, pull power and install the OEM 4G antennas on the router.

Then, power up and run the AT!GSTATUS? one more time.

I agree it does appear your SIM Card is not activated.

But, the modem also appears to not be receiving a signal.

[JamesReinhold]

Hi Jim -

Powered down (removed power) and installed the OEM antennae. Here's the results:

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AT!GSTATUS?
!GSTATUS: 
Current Time:  198		Temperature: 36
Reset Counter: 1		Mode:        ONLINE         
System mode:   WCDMA      	PS state:    Not attached 
WCDMA band:    WCDMA 850  
WCDMA channel: 1007
GMM (PS) state:DEREGISTERED   	LIMITED SERVICE
MM (CS) state: IDLE           	NORMAL SERVICE 

WCDMA L1 state:L1M_PCH_SLEEP  	LAC:         2AEC (10988)
RRC state:   DISCONNECTED   	Cell ID:     0B9183BB (194085819)
RxM RSSI C0:   -87		RxD RSSI C0:  --- 
RxM RSSI C1:    --- 		RxD RSSI C1:  --- 


OK

[JimHelms]

And, you are sure the U.FL connectors are correctly installed on the MC7455 MAIN and AUX antenna ports? And, not mistakenly installed on the GPS antenna port.

If so, the next thing I would try is to reset the modem one more time:

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at!entercnd="A710"
AT!RMARESET=1
at!reset

When the modem comes back online, it will be in QMI mode which is okay for the newer kernel firmware builds.

Make sure the APN is set in the MODEM > CONNECTION PROFILE > APN > broadband

Do a hard reboot.

And run the AT!GSTATUS? one more time.

[JamesReinhold]

Hi Jim. U.FL connectors are correctly installed - I've checked them a couple of times just to make sure they didn't pop off putting the case back together.

I did a reset of the modem:

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at!entercnd="A710"
OK

AT!RMARESET=1
!RMARESET: DEVICE REBOOT REQUIRED

Items Restored:  2153
Items Deleted:   27
Items Skipped:   5

OK

at!reset
OK

Followed by a hard re-boot. Verified APN under Modem -> Connection Profile is "broadband" and pulled status and additional info from Modem -> Debug Information as requested:

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Mon Jul 30 19:36:41 2018 : /dev/ttyUSB2 AT!GSTATUS?
!GSTATUS: 
Current Time:  215		Temperature: 37
Reset Counter: 1		Mode:        ONLINE         
System mode:   WCDMA      	PS state:    Not attached 
WCDMA band:    WCDMA 850  
WCDMA channel: 1007
GMM (PS) state:DEREGISTERED   	LIMITED SERVICE
MM (CS) state: IDLE           	NORMAL SERVICE 
WCDMA L1 state:L1M_PCH_SLEEP  	LAC:         2AEC (10988)
RRC state:   DISCONNECTED   	Cell ID:     0B9183BB (194085819)
RxM RSSI C0:   -90		RxD RSSI C0:  --- 
RxM RSSI C1:    --- 		RxD RSSI C1:  --- 
OK
  
Mon Jul 30 19:36:43 2018 : /dev/ttyUSB2 AT+CPMS="SM"
+CPMS: 0,30,0,30,0,30
OK
  
Mon Jul 30 19:36:44 2018 : /dev/ttyUSB2 AT+COPS=0
OK
  
Mon Jul 30 19:36:45 2018 : /dev/ttyUSB2 AT+CGDCONT=?
+CGDCONT: (1-24),"IP",,,(0-2),(0-4),(0-1),(0-1)
+CGDCONT: (1-24),"PPP",,,(0-2),(0-4),(0-1),(0-1)
+CGDCONT: (1-24),"IPV6",,,(0-2),(0-4),(0-1),(0-1)
+CGDCONT: (1-24),"IPV4V6",,,(0-2),(0-4),(0-1),(0-1)
OK
  
Mon Jul 30 19:36:47 2018 : /dev/ttyUSB2 AT+CGDCONT?;+CFUN?
+CGDCONT: 1,"IPV4V6","broadband","0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0",0,0,0,0
+CFUN: 1
OK
  
Mon Jul 30 19:37:03 2018 : /dev/ttyUSB2 AT+CPMS="SM"
+CPMS: 0,30,0,30,0,30
OK

[JimHelms]

The only other possibilities that come to mind is either the SIM card is NOT activated, or the wrong APN is being used. This is an AT&T SIM card plan that uses the broadband APN?

[JimHelms]

Run the command to see if it is reading the phone number assigned to the SIM card:

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AT+CNUM

Then, to see if the modem is obtaining an IP address, run:

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AT+CGPADDR

[JamesReinhold]

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AT+CNUM
OK

Pretty sure it should come back with the phone number assigned, correct? Along with this, I also noted under Modem -> Network Status -> Modem/SIM Information that the SIM Phone Number field is just "*" (also same for SIM Name).

[JimHelms]

Does the

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at+cpin?

return OK

[JimHelms]

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AT+CNUM
OK

Pretty sure it should come back with the phone number assigned, correct? Along with this, I also noted under Modem -> Network Status -> Modem/SIM Information that the SIM Phone Number field is just "*" (also same for SIM Name).

It should. There is the remote chance the SIM card is defective.

[JimHelms]

While I am skeptical this will correct your issue, my only other suggestion is to download a fresh Router firmware image and reflash the router, and MAKE SURE to UNCHECK the box to Save Settings.

Set the APN in MODEM > CONNECTION PROFILE and hard reboot, and see what happens.

In the end, I think we will find the issue is related to the SIM card, APN or activation.

[JimHelms]

Also sent you a PM.

[JamesReinhold]

Resolved - thanks for the support and assistance! For anyone else with the same presentation of problem, I was able to narrow this down with relative assurance that the issue was with either the SIM or the service provisioned by going through all of the mentioned steps.

The resolution was provisioning the SIM with a different service provider (which eliminated the SIM as the problem). I'm up and running.

[JimHelms]

Resolved - thanks for the support and assistance! For anyone else with the same presentation of problem, I was able to narrow this down with relative assurance that the issue was with either the SIM or the service provisioned by going through all of the mentioned steps.

The resolution was provisioning the SIM with a different service provider (which eliminated the SIM as the problem). I'm up and running.

Not only that, you have learned a lot about configurations and troubleshooting issues. Glad it is all resolved.

[JordanMatthews]

I have a quick question for you. So you said that you resolved the issue. I’m having a similar issue with my mofi4500 router and att prepaid sim purchased from Walmart and activated through Netbuddy. The router only connects to WCDMA 1900 even when directly in town where I know there are several LTE bands available. So did the problem lie on Netbuddies end? If so how did you resolve it? New SIM?

[JamesReinhold]

As I recall NetBuddy wasn't all that helpful in resolving the issue because I wasn't using their equipment. I cancelled within their window of return and got a full refund. I was able to use the same SIM card and provision it through another provider on the AT&T network and it worked fine. PM me if you can't find a different provider or need some help on that end.

[BillA]

Code: Select all

AT+CNUM
OK

Pretty sure it should come back with the phone number assigned, correct? Along with this, I also noted under Modem -> Network Status -> Modem/SIM Information that the SIM Phone Number field is just "*" (also same for SIM Name).

This might be a late reply, but I just read this thread. ;P
In case like this, the first thing you should have done is put the sim card into an ATT or unlocked phone to test it, make sure that at least you can make a call and/or go online. The best way of diagnosing anything for that matter is by the process of elimination. If the sim didn't work in the phone, well then you've just eliminated half of the equation which is the router, then only concentrate on solving the sim/carrier issue, without wasting a bunch of time resetting the router/modem etc, and typing endless useless commands.