I’m going to start out this blog post by saying you should NOT do this. I repeat: do NOT do this. There’s at least a 50/50 chance that if you try this, it won’t work and you could potentially fry your router beyond the point of recovery. You might even start World War III, instantaneously deplete the ozone layer, bring Hitler back to life, and kick off the Apocalypse… all at the same time.
Seriously. Super bad things could happen if you try this. There are far more reliable ways of recovering a bricked router (like using a JTAG or serial cable, for example) that will give you a 100% chance of a successful recovery without toasting your router. I want to get that out in the open right now so that you can’t whine in the comments if you try this and ruin your router. If you do, it’s your own darn fault. You have been warned.
Now, with that all said, I ignored all those warnings and recovered my bricked Netgear WNDR3400 N600 router this week in a few short minutes by shorting two pins on the control board with a tiny jeweler screwdriver.
How did I brick it? It’s a funny story, actually. OK, not really. I had flashed a “mini” trailed version of DD-WRT on the Netgear N600 WNDR3400 router, and was attempting to flash a later “mega” NV64K build of DD-WRT onto it… but apparently the mega build was too big, and I bricked it. So I stumbled across this post by JuanPedro012 on the DD-WRT forums (apparently all of the usernames between JuanPedro001 and JuanPedro011 were already taken?) who described how he also threw caution to the wind and pin-shorted his Netgear WNDR3400 and recovered it. Here are my instructions based on his, with some additional explanations and “safety” measures (even though this isn’t really “safe” for your router).
- Download the two files you’ll need onto your computer (I used a laptop): the stock Netgear firmware for the router from http://www.downloads.netgear.com/files/WNDR3400-V18.104.22.168_15.0.42.chk and the TFTP2 utility (for Windows) from http://www.shadowsoftware.net/shadowgameworld/downloads/tftp2.exe
- With the power cord unplugged, open the router by removing the rubber feet from the four corners on the bottom, then use a small Torx screwdriver remove the four screws under the feet, as well as the two screws in the middle (six screws in total). Here’s what it looks like all opened up:
- Connect an Ethernet cable from the laptop to one of the router’s LAN ports (don’t use the WAN port).
- If using a WiFi network, disable the WiFi adapter on the laptop so that your wireless network IP settings don’t interfere with the local wired connection to the bricked router.
- Configure the local network adapter on the laptop to a Static IP of 192.168.1.25, Netmask 255.255.255.0, and Default Gateway of 192.168.1.1.
- From a command prompt, type ping -t 192.168.1.1 (which will show the laptop attempting to repeatedly ping the bricked router)
- Plug the router in and press in the power button on the back. Watch the command prompt and note that immediately after a specific LED light on the board starts blinking (like it’s sensing network traffic), you’ll see three successful pings at the command prompt before getting the “Destination host unreachable” message again. This small window of opportunity during those three successful pings is when the ping short must be completed. Leave the power cord plugged in, but use the power button on the back of the router to turn it on and off a few times while watching the LED blinking light and corresponding pings, just to get a feel for the timing.
- Locate the two pins closest to the front of the router on the chip designated by the black arrow in this picture from JuanPedro012 (you can click the image for a higher-res version):
- With the router turned off, use a tiny screwdriver (or other piece of metal that is small enough to only touch those two pins) and practice a few times (again, with the router off) to verify that you can quickly touch those two pins at the same time which touching nothing else!
- When you’re ready to go for it, turn the router on, and as soon as you see the LED blinking that corresponds to the successful pings in your command prompt, short the two pins for 1 second, then remove the screwdriver. If the pin short was successful, the router will begin to ping continuously.
- If it doesn’t work, try again a few times (I attempted the pin short 5 or 6 times before it worked for me).
- Once the router is pinging continuously, open the TFTP2 utility and enter 192.168.1.1 in the Server field, then browse for the stock Netgear firmware file in the File field. Hit the Upgrade button. You should see a “success” message within a few seconds.
- Wait for 6 minutes. Seriously. Wait. It doesn’t say this on JuanPedro’s instructions, but you need to do it. Go get a drink. Leave the room. Don’t feel any temptation to power cycle the router, or touch it, or even make eye contact. Let it do its thing for 6 whole minutes. Heck, maybe even wait 10 minutes. You’ll brick it again if you try to power cycle it too early.
- Power cycle the router after 6-10 minutes.
- Try to connect to the router as normal, using the Netgear default of admin/password as the login credentials.
With your router recovered, you can now attempt to re-flash a trailed mini build of DD-WRT specifically for this router per the instructions on the DD-WRT WNDR3400 wiki page, after which you should do a 30/30/30 reset before attempting to flash any other K2.6 build of DD-WRT ending in -nv64k and that will fit in an 8MB flash.
But seriously, you shouldn’t do this. For a safer way to recover a bricked router, search for “JTAG recovery” or “serial recovery” along with the model number of your router. That should shove you in a safer direction. Shorting pins can let out the “magic smoke,” and can destroy your router forever.
I’ve seen reports of this pin shorting working on other Netgear routers, but different models will have different pin locations for the two that you’ll need to short. Don’t guess. Find a post somewhere online that shows the specific pins for your router. This post only shows the ones for the Netgear WNDR3400, since that’s the only Netgear router I’ve personally done this with (and I’ve done it successfully twice).
So again — don’t do this. But if you do, and it works, please tell me about it in the comments. 🙂