RM502Q-AE T-Mobile Loss of Internet but Modem is saying connected

This issue happens to me on tmobile magenta max with the RM-502Q-AE in a ZBT WG1608 router connected via m.2 in LTE FDD mode. it happens sometimes sporadically through the day too, or when i visit certain things. one thing i know for certain triggers this, if i open the ebay app on my iphone connected to the wifi, and navigate to the my purchases page, it insta kills my connection. i have to at+cfun=1,1 to restart the modem every time this happens to get the connection back. also happens when visiting any product page on walmart.com from any device. still shows as connected with signal strength, RSRP, SINR and everything but ping or any connection doesnt work from either a device connected to the network or from the router directly. every time i do that, i can reproduce it. how can i go about troubleshooting this?

Revision: RM502QAEAAR11A02M4G

This router specially versions “V1 and V2” boards have WiFi problems on 5.8G when you install a modem in the M.2 slot. If you move your Modem RM502Q-AE to an external adapter and connect via USB to the ZBT 1608 the problem will go away.

I would suggest stay away from the ZBT WG1608 router.

i agree the wifi is terrible on the wg1608. im not connected via wifi tho. im using the ethernet

How you connect your PC is not the problem. When you use the WiFi is.

In this case if your modem RM502Q-AE is inside the router via the M.2, that causes your problem.

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ah, ok, thank you. i will purchase an external usb modem enclosure and give it a try again

THANK YOU!!! it works!!

I got the external m.2 modem to USB3 enclosure ( USB3 to M.2 Key B 4G 5G Modem Adapter Enclosure with SIM Card Slot - V7 - Sierra Quectel Fibcom SimCOM 5G Supported ) and im using it with a Linksys WRT1900ACSv2 that i flashed to OpenWRT GoldenOrb and it works flawlessly now. I tested using the ebay app and walmart pages and it stays connected now! Such a weird issue.

Why would it be the problem to use the internal M.2 slot?

On some maybe all ZBT WG1608 routers V1 and V2 boards there was a manufacturing problem that ZBT never really clarified as to what caused it. They claimed that the issue was fixed in the new WG1608 board versions, but I doubt it.


I have had this disconnect issue on 2 versions of the ZBT. I have used ZBT 1608 and ZBT 3526 and I have always had intermittent disconnects from the internet. I have used RM500AE and now I am using RM520N. The problem follows the ZBT boards. However, I have never tried another router interface. I may try a different name brand LTE router to see if the problem persists. Didneywhorl definitely knows what I am talking about because I have been trying to solve this problem for over a year on another forum.