Bricked WDR3600 V1

Hi comunity, I am wondering how could I unbrick my WDR3600.Today I updated to a 1gb network and it was only doing 300mbps on OpenWrt firmware.I undestood that if I install stock firmware it should work.But now it is bricked.Actually,im not sure if it is bricked or not,but all the lights are slowly flashing and i cant connect to it via WiFi or Cable.Please help

If you're lucky, tftp push-button recovery might get you booting again, but this functionality was only retrofitted in later (OEM) Firmware updates (newer bootloader versions) and wasn't present in early production runs (use something like wireshark or tcpdump to confirm - or just try your luck). Even if that might get your device back into booting order, there is a huge risk that your faulty flashing method has permanently destroyed the wlan calibration data of your device, rendering the wireless functionality inoperable - unless you have a backup from your own device, this would be permanent and unfixable, but that's something to bother about (and to test) when you've recovered your device.

If tftp push-button recovery isn't available for your device, alternative options might include using a serial console (USB2serial adapter, important 3.3V!) and trying to intercept the bootloader in order to tftpboot a new firmware image manually - or unsoldering the flash chip, rewriting it in a spi flasher (flashrom, ch341a, soic8 clamps) externally and resoldering it afterwards. But - unless you already own the required recovery tools, considering the age of your device and the WAN speed you're aiming for, that might quickly end up more expensive than buying a new device that can handle your WAN speed in the first place - and you're still at risk of having irreparably destroyed your WLAN capability.

If you used sysupgrade or even mtd write firmware, your ART data should still be OK. I usually go right to serial on cases like this.

@slh is right that it's not going to have the horsepower to keep up with a full gigabit ISP line, even with the stock firmware's use of acceleration.

Let's phrase it this way.

A used TL-WDR3600 in working condition sells for ~15-25 EUR, yes - it still won't do the performance you're looking for, just to establish its current value.

  • serial console adapter, around 5 EUR (around 1.50 EUR if you order from China)
  • basic soldering iron, at least 10 EUR (yes, they're not good, but may do; a good soldering station starts around 200 EUR, SMD capable hot air reflow stations much higher than that)
  • soldering tin, flux, solder wick, solder sucker, small parts, another 10 EUR (at least 5)
  • 2.54 mm pin header, ~a few dozens of cents
  • ch341a SPI writer, around 5 EUR
  • SOIC8 test clamp, around 5 EUR

If you already own these things, it's a no-brainer to give them a test.
If you can convince yourself to re-use them for other tasks, you may go this way (really?! if you did, they'd already be sitting on your desk).
If you have to buy them individually, with shipping costs involved (basically no seller will sell you all of them, so multiple shipping costs) - and have to wait 4-8 weeks for them to arrive from china, not so much…

The cheapest device that can cope with your performance requirements would be the Linksys WRT1200AC for 120 EUR (cheaper in the US), although I would consider the WRT3200ACM/ WRT32x the more you get towards 1 GBit/s line speed (because that tends to mean higher expectations from additional services, e.g. VPN, as well).

Trying push-button tftp recovery and hoping for the best in regards to the WLAN calibration data is something you should definitely test. A serial console, maaaybe, but beyond that madness lies.

So, @slh i have everything you said except serial console adapter(i dont know what is that) and also the router when i turn it on all lights start flashing,BUT,when i keep pressed the reset button all the lights turn off and just a light with 2 arrows in a circle(I think its the recovery light) is on but just for a few seconds.Also i dont have the last 2 things you said :((
Thanks for reply guys

See the following links for details regarding serial port / serial adapters:
https://openwrt.org/docs/techref/hardware/port.serial
https://openwrt.org/docs/techref/hardware/port.serial.cables

So i need a special cable and use a JTAG method and also dissasemble my router.
But can i connect to usb because it has 2 of them.

Older versions didn't have tftp recovery enabled in the bootloader, I don't know which hardware revision this started with. That said, if you used stock firmware TP-Link did add this feature for all devices in the end.

Well i used from the first day i bought it OpenWRT

Btw any Idea how to enable WAN on a HG8121H huawei router? it simply wont connect to any internet

@LaeLae Please stick to the topic (WDR3600).
For any other questions which are unrelated to this topic, please open a new one.

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Wireshark or tcpdump can be used to tell you if the router is requesting the recovery firmware via tftp, other than that there are no dependable visible indicators - and even if it fetches the file via tftp, you can't actually be sure what it will do (flashing or discarding) with it.

That's where serial console access can help, but - it's economical viability is borderline (>30% of the price of a used tl-wdr3600 in working order) and even if you would recover your device, it still wouldn't manage to route at 1 GBit/s line-speed.

Hi guys, Ty for all help, I ve sent the router to someone and fixed it with the soldering method.

Again, thank you

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