TM-ac1900 won't enter rescue mode

[WhiskerBiscuit]

My router is on 3.0.0.4.376.3108 and I'm trying to downgrade it to 3.0.0.4_376_1703 so I can install Tomato.

With the power off I'm holding in the reset button, the turning the power on and waiting 15 seconds but the power light never starts to flash. I've tried longer hold times, but nothing. I set my NIC to 192.168.29.2 and can ping 192.168.29.1 so I know I can see the router.

What do I need to do to get this into rescue mode?

Thanks!

 

[WhiskerBiscuit]

Figured it out. Posting instructions and credit for Google

http://slickdeals.net/forums/showpost.php?p=85157887&postcount=5538

I unboxed one today with 3108 firmware. Set out to install DD-WRT on it, but the instructions in the how-to failed to bring it into rescue/restoration mode. Holding down the reset button during power-on would not enable TFTP access. Editing the HTML in the GUI also would not enable telnet access. What finally worked was 1) holding down three buttons- reset, WPS, and wifi on/off - all at the same time 2) powering on 3) waiting a few seconds for fast blinking lights 4) releasing the WPS and wifi buttons, but still holding down reset, 5) as soon as 192.168.29.1 started answered pings, quickly visiting http://192.168.29.1/ to open the mini CFE uploader, 6) submitting the 1703 firmware, and waiting for upload success message 7) finally releasing the reset button. The rest of the how-to worked just fine.

T-Mobile has made it harder to modify the router, but it's still possible.​