Quectel RM502Q-AE No service problem

We have bought 14 RM502Q-AE modules, however one of them is not getting any service whether it is 5G or LTE while others can dial up to 5G cellular network. I had tried updating the firmware and changing the sim card and slots but only this particular module is getting no service at all. Is there a way to solve this problem?

Dear @Lucas_Cheong_Wai
I will share the tool and user guide to backup QCN, please follow it and share the file to us.

Silvia,

I am also having the same problem. Any assistance would be appreciated. I’ve tried the newer firmware as well.

Thank you.

Very Respectfully,
Nick
RM502QAE

Dear @tbird9069
Please query AT+CFUN? and share the response.

CFUN

Dear @tbird9069
Please input “AT+CFUN?” .

See attached image. Sorry I typed it in wrong last time. Any advice would be really appreciated.

CFUN

Dear @tbird9069
It seems QCN files was earsed, if restore with my QCN files, the performance will be worse than before.
Please note this.

You are amazing. It worked and connected, but it only connects for 10 seconds and then restarts… I hooked it up to a reliable power source too. Also the speed is slower, do you know why that is?

Thank you again for all your help. Can’t thank you enough.

v/r

Nick

Dear @tbird9069
Every module will be calibrated before shipment, the QCN files are different.

If you restore the QCN from my module, the performance will be worse than before.

Silvia,

I recovered my QCN file before installing yours. Does that help me at all? Can I send that in for repair? What firmware do you recommend I use?

Thank you again for your help.

Dear @tbird9069
If QCN file is correct, you can try to restore, and check whether it register.

+CFUN:5 means module has problem.
Normally, it will be +CFUN:1.

It is recommended to use the latest firmware.