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RT-AC68U Solid USB 2.0 light

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AceOfSpades

New Around Here
Searched all over but haven't found a solution to this problem. I had the router going for about a week and it was working like a champ, and then it went down one night. Now I can't access the router via web, reset it, or get the router to go into rescue mode. The only other LEDs that come on other than the solid USB 2.0 LED (nothing is plugged into either usb port) are the LAN ports if a cable is connected.
Backstory: flashed a TM-AC1900 to stock ASUS firmware, and then flashed the latest Merlin firmware and it worked great using very basic settings.
I'm able to ping the router, but can't use the ASUS Firmware Restoration program to try and flash because I can't get into rescue mode. Any help would be appreciated! Thanks.
 
I have the same problem, but with an asus AC-1900P. My background is a little more basic: received the router, and I updated to the standard ASUS firmware. It rebooted once, working fine. then I turned it off to move it where I wanted, and would only boot to the USB light. No recovery mode was possible; the LAN lights would work when plugged in, but that was it.
I let it sit around while I hid under my bed sheets hoping all technology would go away. Eventually, it would boot differently, showing a solid power light but nothing else, and I was able to get into recovery mode and re-flash with the firmware recovery, and it worked!
... Then a new firmware came out, and since I LOVE making the same mistake, I tried to flash that through the ASUS software. Same again; flashed, rebooted once, Worked!
went to move the router, and it stopped working; Only the USB 2.0 light comes on now.

Since, I've tried everything. let it sit for a couple of days like last time, 30-30-30 resets, resting holding the WPS and/or Wifi on/off button, and still all I get is the USB 2.0 light.

I've noticed that when a LAN port is connect, it will only stay up for a few seconds at a time, as if the router is constantly rebooting. I've also, somehow, sometimes, gotten it to turn onto the power light being solid (but not in recovery), although Wifi does not turn on, and it is never visible from a computer.

It came back from this state once, but I'm not sure how/what I did to do it. :-/ Any help would be greatly appreciated!
 
I experienced the same issue but mine shutdown due to power outage. When the power came back, the router would not start. The LAN and WAN LEDs are working but it would not provide a valid IP address. The WiFi would not work.. no WiFi LED. The USB 2.0 would be solid and then the power will light up. That's about it. It just suddenly worked one morning. I was so ready to buy a new router but it just started to work again. I am not sure what is causing this and why it just started to work.
 
For what is worth for you guys:

Recovery mode:
  1. Have a firmware file available, ending with the extension .trx
  2. Power down the router.
  3. Remove USB memory devices (if any).
  4. Press and hold the reset button, at the same time power up the router.
  5. Wait for slow flashing Power LED.
  6. Release the reset button.
  7. Set your computer to a fixed IP address, such as 192.168.1.100 / 255.255.255.0.
  8. Hardwire your computer to the router.
  9. Start the Firmware Restoration utility.
  10. Follow the instructions to locate the firmware file and start the installation.
  11. Wait for the Firmware Restoration utility to finish.
  12. Access the router at the default IP address 192.168.1.1 and admin/admin
  13. Manual configure the router again (do NOT load an old configuration backup file).
  14. Optional: delete the wireless connection profiles on your computers and connect again.

Specially when you can Ping the router:
After step 8 you can also start a web browser and open http://192.168.1.1
This shall open the ASUSTeK - CFE miniWeb Server, from there you can Upload a Firmware File, Reboot or Restore default NVRAM values.

upload_2017-2-25_9-39-23.jpeg
 
Last edited:
Thanks for your post.

Unfortunately, as we mentioned, our routers will NOT enter rescue mode, therefore no access to the firmware restoration tool and the other helpful bits.

the issue is that all attempts at booting leave us with the USB 2.0 light on solid, nothing else. I cannot speak for others, but for me plugging in a LAN cable is recognized, but it will not keep a connection for more than a few seconds, as if the router is restarting constantly.

This happened to me once before, and after a few days it worked just fine-- but that doesn't make any sense to my not-so-technical knowledge.
 
Thanks for your post.

Unfortunately, as we mentioned, our routers will NOT enter rescue mode, therefore no access to the firmware restoration tool and the other helpful bits.

the issue is that all attempts at booting leave us with the USB 2.0 light on solid, nothing else. I cannot speak for others, but for me plugging in a LAN cable is recognized, but it will not keep a connection for more than a few seconds, as if the router is restarting constantly.

This happened to me once before, and after a few days it worked just fine-- but that doesn't make any sense to my not-so-technical knowledge.

Can you ping the router? If you can, what is TTL value? You sure your AC adapter is good and plug in
tight to the wall outlet or power bar?
 
Have you tried this sequence:
  1. Turn off the router.
  2. Press and hold the WPS button.
  3. Turn on the router.
  4. Wait about 10 seconds.
  5. Release the WPS button.
Try to access the router at 192.168.1.1
 
It's toast. I've had a couple in that state. No serial output at all.
 
I just joined and was about to create a new thread when I saw this one. I've got the same issue. Wife was working online today when her Internet went down. Now I get LAN and WAN activity lights, solid USB 2.0, nothing else. No recovery mode access, DHCP not working, nada. It was great for the two weeks it lasted.
 
I'm having exactly the same issue as mentioned here - my router was powered down for a few months (shifting around, wasn't using it). Today when I tried to turn it on, I only get a solid USB 2.0 light, and a light when I plug in an ethernet cable. No wifi signal either. When I hook up an ethernet cable, I just get some autogenerated IPv4 address. I can't access 192.168.1.1 or anything else. I've tried hard resetting, 30-30-30 reset, reset using the WPS button but nothing seems to work.

Is the router fried, or is there anything else I can do?
 
Wondering at what phase the CFE loader becomes available... On a 56U thread

https://www.snbforums.com/threads/r...nal-firmware-374-291.13628/page-2#post-101361

CFE can sometimes be accessed with a serial cable when other methods fail. I have a cable on order but don't want to crack my case without confirmation it's worked before or until I reach a point with Asus that they won't work a warranty repair/replacement. Mine is a rebranded TM-AC1900, but T-Mobile has already booted me over to Asus support.
 
The same thing just happened to me with same router. I've had it 3 years and 4 months. I flashed it with latest merlin a few months ago. Internet suddenly went out a few days ago and the only thing I get when I power up is a solid USB 2.0 light (and LAN ports if something is plugged in). Any body have solution? Would trying to serial in be worth it? I'm not even sure how to open the case. Don't want to damage it since I can at least get a few bucks for it on ebay.

I measured the voltage on the Asus 19v power adapter and got 18.6v. Is this within range? Or does this indicate maybe I need a new power adapter?
 
I also had 18.6V on my adapter and just assumed that was within operational tolerance. If you have something putting out a little more you've got nothing to lose by trying.

T-Mobile support sent me to Asus for repair, who set up an RMA under the serial number I gave. The actual RMA I received had a serial number in a different format than the one I had supplied, so I assumed it was automatically converted by Asus from a T-Mobile number to an Asus cross-reference.

I shipped to Asus, and they sent it back untouched saying they did not repair T-Mobile routers.

I bought a USB to TTL adapter for cheap but never was able to talk to the router.

Don't remember the details of how I got the case apart but seems like it was just mainly some careful prying and maybe a minimal number of screws in the base. No damage doing so.

Ended up just tossing mine. Bought a Nighthawk and am happy with it.
 
So I got it open. You have to take off the sticker on the back and underneath are two screws. Then you can push a thin screwdriver through the holes to begin pulling the case apart from the snaps.

Looking at the logic board, I discovered that the power LED does light up, but very faintly, so it was not visible when the case was on.

I tried to serial in with the UART adapter, but I get no response from the unit.

I don't know enough about electronics to go further, so I also have a Nighthawk on the way. Too bad, this was a GREAT router while it lasted.
 
I know this is old, but I believe I may have figured out the missing piece. As counter-intuitive as it may seem..
Turn off the router via the power button, and then unplug the power cord.
Hold down the reset button
Continue to hold the reset button while you plug the power cord back in
Continue to hold the reset button while you power the router on via the power button
Hold the reset button for about 5 - 10 seconds..until AT LAST.. that power LED starts blinking.

I stumbled on the answer from a different post on how to enter recovery mode on a different Asus Router model.
I duplicated this process 3 times, and it worked each time.
I had thought the router was lost, but boxed it back up and kept it in the closet, as I tend to have a hard time throwing things like that away.
With the new AIMesh network option, I decided to pull it out and see if I could get lucky. I did. I ran the recovery utility and it worked like a charm.

AIMesh..here I come..
 
I know this is old, but I believe I may have figured out the missing piece. As counter-intuitive as it may seem..
Turn off the router via the power button, and then unplug the power cord.
Hold down the reset button
Continue to hold the reset button while you plug the power cord back in
Continue to hold the reset button while you power the router on via the power button
Hold the reset button for about 5 - 10 seconds..until AT LAST.. that power LED starts blinking.

I stumbled on the answer from a different post on how to enter recovery mode on a different Asus Router model.
I duplicated this process 3 times, and it worked each time.
I had thought the router was lost, but boxed it back up and kept it in the closet, as I tend to have a hard time throwing things like that away.
With the new AIMesh network option, I decided to pull it out and see if I could get lucky. I did. I ran the recovery utility and it worked like a charm.

AIMesh..here I come..

I have an asus ac68 router with the same symptom as posted on that topic. At that moment he is with an electronics technician who told me something about an electronic component controller next to the USB2 led.
Was the symptom of your router the same as the one on the topic? just led USB2 on?
 
Did anyone ever find a fix for this? Woke up to my AC68P doing this now. Originally the wifi was broadcasting but I was unable to connect to it. After power cycling now only the USB 2.0 light is on (with nothing plugged into it). Plugging a laptop into the lan still isn't able to bring up the interface. Reset, hard reset and recovery mode have no effect.
 

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