I thought I'd document the symptoms of a power supply failure in a wrt54g v1.0.  It can look suspiciously like bad firmware, but the regular tricks to debrick the router will not help in this case, because it's not the firmware.  It's actually the power supply.  And from reading around the Internet, it seems like these old supplies are starting to go out.

Symptoms of a bad power supply:

The power and diag lights may blink very quickly, then all will go dark  The power supply cannot supply the juice to get things going.

The power and diag lights may come on solid, and nothing else.  The ethernet lights will not come on when a cable is plugged in.  This one looks suspiciously like bad firmware, because the lights come on fully but stay stuck.  Actually, the PS can supply enough juice to turn it on, but the board cannot boot - i suspect it's stuck in a cycle, trying to boot but running out of power.

In another scenario, the power and diag lights came on solid, and all the ethernet lights flashed (like a normal bootup).  Then all the lights flashed again... and again.  Same situation as above - stuck in a reboot cycle because the PS cannot supply enough power to boot the board.

Solution:

Obviously, try a new power supply.  It MUST be able to supply the rated power.  These routers really need it.  If the power supply cannot supply enough juice, the above problems will occur.

The v1.0 wrt54g needs a 5V supply at 2 amps (or more).  I believe v1.1 and above use a 12V, 1 amp supply.  You can sometimes find random power supplies at second hand stores.  I found one for $2.  It doesn't matter if the plug doesn't fit - cut the old one off your dead power supply and wire it to the new supply.

If you absolutely can't find a 5V, 2 amp supply, you could substitute a supply with a little more voltage and a little less current.  THIS WILL LIKELY REDUCE THE LIFE OF YOUR ROUTER, and don't say I didn't warn you, and use at your own risk, etc.  But it may work.  I used up to 12V on the router (for a short time) and it seemed to work.  A 5V, 2A supply can produce up to 10W.  Equivalently, a 10V, 1A supply can produce up to 10W.

Again, this is just informational.  Use at your own risk!

Enjoy!
-Jeff

(Last edited by jcw on 23 Mar 2006, 18:07)

Thanks a lot, jcw ! I recently bought a WRT54G v1.0 on ebay - and when it arrived, it wouldn't power up. Same exact symptoms. I was getting ready to crack the box open when I found this post.

Luckily, I also own a NSLU2 - which uses the same 5V/2A power supply. Swapped the WRT PS for the NSLU one - it booted up.

So now to get a new PS for it . . . as said, thanks for the post - it did indeed help me

I'm surprised why this comes up so often, and people seem to think they need the factory replacement wart to fix it. If you lost your CD-player adapter, you would just to Wal-Mart and find a generic that will fit.

Why do you think electronics stores stock these generic replacement adapters? Because they work.  The WRT series uses an M-size connector.  Just get one with an end that fits, right voltage, and a wart capable of same or more amperage as original and that's all you need to worry about.