Hi,
I am experiencing an issue where a specific nRF9151 SMA DK kit is stuck in an infinite network registration loop. The modem continuously reports +CEREG: 2 (Not registered, searching) in LTE mode: 7 (LTE-M), but it never transitions to the successful +CEREG: 1 or 5 states.
Analyzing the debug logs, I notice that the RF hardware successfully scans and detects local antennas, but the network never accepts the registration.We have other identical nRF9151 SMA DK kits in our lab. When we flash the exact same firmware binary and insert the exact same SIM card into the other kits, they register to the LTE-M network successfully (+CEREG: 1 or 5) in seconds. Therefore, we have completely ruled out any issues with the SIM card subscription, APN configuration, local network coverage, or application code.
We have tested this specific board continuously for several hours, and it never manages to register.
-Hardware & Software Environment: Development Kit: nRF9151 SMA DK
-Modem Firmware Version: mfw_nrf91x1_2.0.4 (Confirmed via AT+CGMR)
-SIM Card / Carrier: Movistar KITE
[00:00:14.300,567] <dbg> lte_lc: lte_lc_connect: Connecting synchronously [00:00:14.300,598] <dbg> os: z_impl_k_mutex_lock: 0x2001ba58 took mutex 0x2001ca00, count: 1, orig prio: 0 [00:00:14.309,692] <dbg> os: z_impl_k_mutex_unlock: mutex 0x2001ca00 lock_count: 1 [00:00:14.309,722] <dbg> os: z_impl_k_mutex_unlock: new owner of mutex 0x2001ca00: 0 (prio: -1000) [00:00:14.309,722] <dbg> os: z_impl_k_mutex_lock: 0x2001ba58 took mutex 0x2001ca00, count: 1, orig prio: 0 [00:00:14.310,028] <dbg> os: z_impl_k_mutex_unlock: mutex 0x2001ca00 lock_count: 1 [00:00:14.310,058] <dbg> os: z_impl_k_mutex_unlock: new owner of mutex 0x2001ca00: 0 (prio: -1000) [00:00:14.310,089] <dbg> os: z_impl_k_mutex_lock: 0x2001ba58 took mutex 0x2001ca00, count: 1, orig prio: 0 [00:00:14.310,455] <dbg> os: z_impl_k_mutex_unlock: mutex 0x2001ca00 lock_count: 1 [00:00:14.310,485] <dbg> os: z_impl_k_mutex_unlock: new owner of mutex 0x2001ca00: 0 (prio: -1000) [00:00:14.310,485] <dbg> os: z_impl_k_mutex_lock: 0x2001ba58 took mutex 0x2001ca00, count: 1, orig prio: 0 [00:00:14.310,913] <dbg> os: z_impl_k_mutex_unlock: mutex 0x2001ca00 lock_count: 1 [00:00:14.310,943] <dbg> os: z_impl_k_mutex_unlock: new owner of mutex 0x2001ca00: 0 (prio: -1000) [00:00:14.310,943] <dbg> os: z_impl_k_mutex_lock: 0x2001ba58 took mutex 0x2001ca00, count: 1, orig prio: 0 [00:00:14.349,212] <dbg> nrf_modem: cfun_callback: CFUN callback 0x5b47b [00:00:14.349,243] <dbg> os: z_impl_k_mutex_unlock: mutex 0x2001ca00 lock_count: 1 [00:00:14.349,273] <dbg> os: z_impl_k_mutex_unlock: new owner of mutex 0x2001ca00: 0 (prio: -1000) [00:00:14.349,273] <dbg> lte_lc: cfun_mode_set: Functional mode set to 1 [00:00:16.515,106] <dbg> at_monitor: at_monitor_task: AT notif: +CEREG: 2,"2A3C","0138AA04",7 [00:00:16.515,136] <dbg> at_monitor: at_monitor_task: Dispatching to 0x4ba41 [00:00:16.515,197] <dbg> lte_lc: at_handler_cereg: +CEREG notification: +CEREG: 2,"2A3C","0138AA04",7 [00:00:16.515,258] <dbg> lte_lc: parse_cereg: Network registration status: 2 [00:00:16.515,380] <dbg> lte_lc: parse_cereg: LTE mode: 7 [00:00:56.016,052] <dbg> at_monitor: at_monitor_task: AT notif: +CEREG: 2,"2A3C","013C6D05",7 [00:00:56.016,082] <dbg> at_monitor: at_monitor_task: Dispatching to 0x4ba41 [00:00:56.016,113] <dbg> lte_lc: at_handler_cereg: +CEREG notification: +CEREG: 2,"2A3C","013C6D05",7 [00:00:56.016,174] <dbg> lte_lc: parse_cereg: Network registration status: 2 [00:00:56.016,296] <dbg> lte_lc: parse_cereg: LTE mode: 7 [00:01:12.440,093] <dbg> at_monitor: at_monitor_task: AT notif: +CEREG: 2,"2A3C","0138AA04",7 [00:01:12.440,124] <dbg> at_monitor: at_monitor_task: Dispatching to 0x4ba41 [00:01:12.440,185] <dbg> lte_lc: at_handler_cereg: +CEREG notification: +CEREG: 2,"2A3C","0138AA04",7 [00:01:12.440,216] <dbg> lte_lc: parse_cereg: Network registration status: 2 [00:01:12.440,368] <dbg> lte_lc: parse_cereg: LTE mode: 7 [00:01:50.088,897] <dbg> at_monitor: at_monitor_task: AT notif: +CEREG: 2,"2A3C","013C6D05",7 [00:01:50.088,928] <dbg> at_monitor: at_monitor_task: Dispatching to 0x4ba41 [00:01:50.088,989] <dbg> lte_lc: at_handler_cereg: +CEREG notification: +CEREG: 2,"2A3C","013C6D05",7 [00:01:50.089,019] <dbg> lte_lc: parse_cereg: Network registration status: 2 [00:01:50.089,172] <dbg> lte_lc: parse_cereg: LTE mode: 7 [00:02:04.521,484] <dbg> at_monitor: at_monitor_task: AT notif: +CEREG: 2 [00:02:04.521,514] <dbg> at_monitor: at_monitor_task: Dispatching to 0x4ba41 [00:02:04.521,545] <dbg> lte_lc: at_handler_cereg: +CEREG notification: +CEREG: 2 [00:02:04.521,606] <dbg> lte_lc: parse_cereg: Network registration status: 2 [00:02:04.521,636] <dbg> lte_lc: parse_cereg: LTE mode not found, error code: -5
Thank you in advance for your assistance with this issue.
Kind regards,