Router half-bricked, can occasionally start via 30-30-30

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jrat
jrat's picture
Router half-bricked, can occasionally start via 30-30-30

Hopefully this isn't out of the scope of help I might recieve here, as I believe this is a hardware level issue.

I received this router (WGL614 v8) from a friend, who said it died out on him via power surge.  I do some occasional electronics repairs (TVs, component level on pc motherboards, etc), so I figured I'd have a shot at this. 

After fiddling with it for awhile, I found that running a 30-30-30 reset sometimes allowed it to boot up and run just fine.  No problems or quirks to be seen.  I went ahead and flashed to the newest NG/stock firmware to see if it'd help, but it did not. It did restart itself after the flash and run fine - it only fails again once power is completely removed.

After removing power, it wouldn't start again that day, so it just sat for awhile.

I decided today to tinker some more and it started right up via 30-30-30, so I went ahead and tossed DD-WRT onto it via the UI.  The flash went fine, and it rebooted to the DD-WRT UI with no issues - good wireless, no problems.  I had hoped that maybe the bootloader routines were somehow different (who knows?) and would sidestep the problem.  Unfortunately, once removing and reapplying power, it once again wouldn't start.

It seems to start up best for me after sitting for awhile.  30-30-30 seems to only work a couple times before I need to put it down and let it rest awhile again.

A failed startup will be either 1.) all LEDs lit -OR-  2.) All LEDs will flash once, and it'll look like it's starting up normally, and hang with yellow status (checkmark) light, and solid green power. In this second state, the connector LEDs will respond to cables being plugged/unplugged.  

In both forms of failure, I get about 99% packet loss while pinging. Some do come back, however.

 

I'm not expecting anyone to give me a magic fix here.  Rather, I'm wondering if anyone may know this device well enough to point me in the right direction? 

Does the serial output show the boot process?  This way I could possibly see what it's hanging on, and why it might not do so via 30-30-30.   I should have a cable for this in hand shortly.

This is just a project, if I can't get it going - oh well.  No loss.  I'd like the fun of trying though.

 

Thanks for any help!

Nachi
Nachi's picture
Serial port output should

Serial port output should show some messages unless the problems occur at the very beginning of the CFE boot loader.
Were you managed to get any serial port connection. The symptoms are indicative of hardware failure but its almost impossible to guess what that could be.

Would be interested to know if you find anything.

jrat
jrat's picture
I've done alot of

I've done alot of experimenting since posting, and I'm pretty sure at this point there is a hardware failure of some sort.  Possibly the flash chip.

I threw together an LVTTL - rs232 interface cable using a max3232 IC (free sample, might be good to know for those of you that are cheap like me Money mouth).  Worked like a charm.

When the boot process fails with a full firmware loaded, it almost always just stops at loading wl.o (using DD-WRT or stock-NA.) 

The curious thing is that when the flash is erased and rewritten, the unit will power up and run perfectly every single time on the first restart.  Once it is reset either via the GUI or hard reset, it will again fail until reflashed.  This, combined with the fact that a 30-30-30 sometimes allows it to boot, says to me that it's having issues writing or storing the NVRAM data (bad bytes/blocks).

At this point, I've erased the wholeflash several times and loaded the CFE/Config data, to see what the results are.  Nothing different.  I am having issues getting the LAN ports ports to become active at times (after a reboot), which means I'm stuck with JTAG most of the time.  Many flashes with JTAG come out corrupt, and have to be redone.

I'm trying now to get everything loaded, and clear the NVRAM via serial connection, and see if it allows it to boot.

I'd like to emphasize though, that when this thing is powered up and running, there seem to be no issues with it what-so-ever.  Good radio. The GUI navigates smoothly.  All LAN ports function correctly.  Again, I NEVER have issues after a fresh flash. Not once.

 

Has anyone ever experimented with alternate flash chips on one of these?  I know it's possible with some other routers, and I know the 5354 chip supports both serial and parallel flash.  It would seem to me that I could possibly use an SD card in SPI mode, provided I could get tjtag to work with it.