Always searching for network in M66 R2.0

IoT Modules GSM Module
1

Hi,
I’m using M66 R2.0 for an IoT application. I tested MQTT on M66 R2.0 dev board using AT commands and it works.

I checked same antenna and SIM network using dev board it works.

After doing same on custom M66 based PCB, It gets stuck on network registration.

AT command log:

/* Use ATI to get module information of Manufacturer ID, Device modle and Firmware version */
[2021-09-14 09:28:19:979_S:] ATI
[2021-09-14 09:28:20:049_R:] ATI
[2021-09-14 09:28:20:049_R:] Quectel_Ltd
[2021-09-14 09:28:20:049_R:] Quectel_M66
[2021-09-14 09:28:20:049_R:] Revision: M66FBR03A06

[2021-09-14 09:28:20:049_R:] OK

/* Use AT+CPIN? to query the SIM card status : SIM card inserted or not, locked or unlocked */
[2021-09-14 09:28:22:295_S:] AT+CPIN?
[2021-09-14 09:28:22:374_R:] AT+CPIN?
[2021-09-14 09:28:22:374_R:] +CPIN: READY

[2021-09-14 09:28:22:374_R:] OK

/* Use AT+CSQ to query current signal quality */
[2021-09-14 09:28:22:376_S:] AT+CSQ
[2021-09-14 09:28:22:449_R:] AT+CSQ
[2021-09-14 09:28:22:449_R:] +CSQ: 17,0

[2021-09-14 09:28:22:449_R:] OK

/* Use AT+CREG? /AT+CGREG? to query the network registration status. */
[2021-09-14 09:28:22:454_S:] AT+CREG?
[2021-09-14 09:28:22:570_R:] AT+CREG?
[2021-09-14 09:28:22:570_R:] +CREG: 1,2

[2021-09-14 09:28:22:570_R:] OK
[2021-09-14 09:28:22:573_S:] AT+CGREG?
[2021-09-14 09:28:22:694_R:] AT+CGREG?
[2021-09-14 09:28:22:694_R:] +CGREG: 0,2

[2021-09-14 09:28:22:694_R:] OK

/* Use AT+COPS? to query current Network Operator */
[2021-09-14 09:28:22:699_S:] AT+COPS?
[2021-09-14 09:28:22:820_R:] AT+COPS?
[2021-09-14 09:28:22:820_R:] +COPS: 0

[2021-09-14 09:28:22:820_R:] OK

/* Use AT+CPIN? to query the SIM card status : SIM card inserted or not, locked or unlocked */
[2021-09-14 09:28:26:071_S:] AT+CPIN?
[2021-09-14 09:28:26:147_R:] AT+CPIN?
[2021-09-14 09:28:26:147_R:] +CPIN: READY

[2021-09-14 09:28:26:147_R:] OK

/* Use AT+CSQ to query current signal quality */
[2021-09-14 09:28:26:151_S:] AT+CSQ
[2021-09-14 09:28:26:268_R:] AT+CSQ
[2021-09-14 09:28:26:268_R:] +CSQ: 17,0

[2021-09-14 09:28:26:268_R:] OK

/* Use AT+CREG? /AT+CGREG? to query the network registration status. */
[2021-09-14 09:28:26:275_S:] AT+CREG?
[2021-09-14 09:28:26:394_R:] AT+CREG?
[2021-09-14 09:28:26:394_R:] +CREG: 1,2

[2021-09-14 09:28:26:394_R:] OK
[2021-09-14 09:28:26:401_S:] AT+CGREG?
[2021-09-14 09:28:26:518_R:] AT+CGREG?
[2021-09-14 09:28:26:518_R:] +CGREG: 0,2

[2021-09-14 09:28:26:518_R:] OK

/* Use AT+COPS? to query current Network Operator */
[2021-09-14 09:28:26:525_S:] AT+COPS?
[2021-09-14 09:28:26:644_R:] AT+COPS?
[2021-09-14 09:28:26:644_R:] +COPS: 0

[2021-09-14 09:28:26:644_R:] OK

3

Hi Suman_Kumar:
Please check the following AT commands:
AT+QBAND?
AT+QLOCKF?
Please confirm whether you can access the Internet normally when the card is inserted in the mobile phone.

4

Internet is working on smartphone and dev board using same sim.
Also upgraded latest firmware and tested, same network registration issue.
Log:
AT+QBAND?
+QBAND: “GSM850_EGSM_DCS_PCS_MODE”
OK
AT+QLOCKF?
+QLOCKF: 0
OK
image

5

Please contact support@quectel.com or local FAE for more help.This problem needs R&D to analyze the log.