Strange used batch of EM7511 modules

Hello, I have a dozen or so used EM7511 Modules that all show similar info. I believe these were sourced from a chinese supplier and am leaning towards them being engineering samples, but not really sure… If I don’t do anything but configure them, they appear to work ok, but when I try to update firmware, they appear to succeed then get stuck in low power mode. Any thoughts?

ati
Manufacturer: Sierra Wireless, Incorporated
Model: EM7511
Revision: SWI9X50C_01.06.05.00 2df3a4 jenkins 2018/05/08 19:40:17
IMEI: 001027009999999
IMEI SV: 6
FSN: YT942770230315
+GCAP: +CGSM

at!gstatus?
!GSTATUS:
Current Time: 444 Temperature: 21
Reset Counter: 1 Mode: LOW POWER MODE

at!pcinfo?
State: Low Power Mode
LPM voters - Temp:0, Volt:0, User:0, W_DISABLE:0, IMSWITCH:1, BIOS:0, LWM2M:0, OMADM:0, FOTA:0, RFCAL:0
LPM persistence - None

at!image?
TYPE SLOT STATUS LRU FAILURES UNIQUE_ID BUILD_ID
FW 1 EMPTY 0 0 0
FW 2 EMPTY 0 0 0
FW 3 EMPTY 0 0 0
FW 4 EMPTY 0 0 0
Max FW images: 4
Active FW image is at slot 255

TYPE SLOT STATUS LRU FAILURES UNIQUE_ID BUILD_ID
Max PRI images: 50

what is the return of the following?

AT!ENTERCND=“A710”
AT!impref?

at!impref?
!IMPREF:
preferred fw version: 01.05.01.00
preferred carrier name: GENERIC
preferred config name: GENERIC_001.028_000
current fw version: 01.06.05.00
current carrier name:
current config name:

fw version mismatch
carrier name mismatch
config name mismatch

OK

The FW is not matching with the PRI configuration.

Which FW are you downloading to it?

I have tried several versions with the same results, including SWI9X50C_01.14.02.00. The above impref was on a module that I tried installing an older firmware on.

Below is how they came to us. Functional, but once firmware upgrade is performed they go into lpm

ati
Manufacturer: Sierra Wireless, Incorporated
Model: EM7511
Revision: SWI9X50C_01.06.05.00 2df3a4 jenkins 2018/05/08 19:40:17
IMEI: 001027009999999
IMEI SV: 6
FSN: YT845488150310
+GCAP: +CGSM

OK
at!entercnd=“A710”
OK
at!gstatus?
!GSTATUS:
Current Time: 745 Temperature: 23
Reset Counter: 1 Mode: ONLINE
System mode: LTE PS state: Not attached
LTE band: No band LTE bw: 1.4 MHz
LTE Rx chan: 0 LTE Tx chan: 18000
LTE SSC1 state:NOT ASSIGNED
LTE SSC2 state:NOT ASSIGNED
LTE SSC3 state:NOT ASSIGNED
LTE SSC4 state:NOT ASSIGNED
EMM state: Deregistered No Cell
RRC state: RRC Idle
IMS reg state: No Srv

PCC RxM RSSI: 0 PCC RxM RSRP: 0
PCC RxD RSSI: 0 PCC RxD RSRP: 0
Tx Power: – TAC: 0000 (0)
RSRQ (dB): 0.0 Cell ID: 00000000 (0)
SINR (dB): 0

OK
at!impref?
!IMPREF:
preferred image setting does not exist
current fw version: 01.06.05.00
current carrier name:
current config name:

fw version mismatch
carrier name mismatch
config name mismatch

OK

Here is an addition to my last message… seems pretty strange

at!priid?
PRI Part Number: Unknown
Revision: Unknown
Customer: Unknown

Carrier PRI: None

OK

Are you using windows exe to upgrade?

Yes, using windows. Not really sure what else to try…

Finally got this to work, after too many hours of messing around. If I would just have one of these modules, definitely wouldn’t have bothered.

I’ll include a brief overview of the steps that it takes to get one of these em7511 possibly engineering samples to work with the current firmware 1.14.02 using Putty…

  1. Set AT!USBCOMP=1,3,100D
  2. AT!RESET
  3. Update firmware with windows exe
  4. AT!ENTERCND=“A710” followed by AT!USBPID=9091,9090
  5. Enter engineering mode - won’t go into how to do this. Involves at!openlock? and giving the module the correct response
  6. AT!IMPREF=“01.14,02,00,”",""
  7. AT!RESET

Modem should now be out of LPM due to the FW/Carrier/Config Mismatch and be on the newest firmware.

Was this worth the time? Maybe since I have a bunch of these modules. Definitely not if you’re trying to save a couple bucks on a single unit. Also, this works for my specific problem on my specific batch, no guarantee you are having the same problem.