Posted: Sun Apr 02, 2017 13:21 Post subject: Is it possible to replace a worn out flash chip on a WRT54G?
Hi all.
I have an old linksys WRT54G v3.1 (aged more than 10 years) which I flashed with DD-WRT v24-sp2. I suspect the EEPROM chip is wearing out or has already worn out. Symptoms are:
- lost its configuration completely and returned to factory settings
- wireless security don't survive a reboot or don't work, making plain, unsecure access the only possible way.
FTR the device loses its configuration especially when I turn the power off for the night, for instance. Rebooting doesn't seem to exhibit any trouble.
What enforces my deduction is I kept the logging option (Security > Firewall > Log: enable) active for several years, which I know is prone to destroy the flash memory progressively. All in all I'm not so much interested in knowing if my deduction is correct, I'd just like to know if it's possible to replace the flash chip on that device.
Assume I'm used with SMD soldering and I am equipped with the appropriate soldering/desoldering tools to manipulate SMD components. Can it be done at all? Are there any precautions, other than the usual anti-static measures?
Joined: 04 Jan 2007 Posts: 11564 Location: Wherever the wind blows- North America
Posted: Sun Apr 02, 2017 18:49 Post subject: Re: Is it possible to replace a worn out flash chip on a WRT
VinzC wrote:
Hi all.
I have an old linksys WRT54G v3.1 (aged more than 10 years) which I flashed with DD-WRT v24-sp2. I suspect the EEPROM chip is wearing out or has already worn out. Symptoms are:
- lost its configuration completely and returned to factory settings
- wireless security don't survive a reboot or don't work, making plain, unsecure access the only possible way.
FTR the device loses its configuration especially when I turn the power off for the night, for instance. Rebooting doesn't seem to exhibit any trouble.
What enforces my deduction is I kept the logging option (Security > Firewall > Log: enable) active for several years, which I know is prone to destroy the flash memory progressively. All in all I'm not so much interested in knowing if my deduction is correct, I'd just like to know if it's possible to replace the flash chip on that device.
Assume I'm used with SMD soldering and I am equipped with the appropriate soldering/desoldering tools to manipulate SMD components. Can it be done at all? Are there any precautions, other than the usual anti-static measures?
Thanks in advance for any hint and/or suggestion.
Yeah...they can be changed...carefully.
use a solder iron of relatively low wattage. (25-30W max) Lay down a bead of solder globbing across all the pins of the chip. Now...carefully...heat one side of the chip at a time and carefully pry up that side of the chip with gentle pressure (with a narrow flat blade screwdriver) without lifting the pads....now using pliers (small needle-nose) lift gently on the other side as you apply heat to all the pins on that side.
Once the chip is removed, now use braided solder wick to clean off solder from the pads left from the previous removal step. Now lay your new chip on the pads...using lots of solder flux and solder just solder the pins on opposite corners first making sure you have your pin to pad alignment correct. Once satisfied you are aligned...now do the same thing you did during the desolder process...lay down a big glob strip of solder over all the pins at once. (all pins connected together essentially) (do one side at a time)...then using the solder braid again clean up all this globbed solder. Just enough solder will be left behind to make contact with all the pins to pads. Use a magnifying glass or jewelers loop to verify all pin/pad contact and no solder crossing between ANY pins.
That's about it....take your time....its possible...I've done chip replacement before...it takes about an hour for a flash chip.
Good luck.
redhawk _________________ The only stupid question....is the unasked one.
Joined: 04 Jan 2007 Posts: 11564 Location: Wherever the wind blows- North America
Posted: Tue May 09, 2017 20:30 Post subject:
VinzC wrote:
I thought I'd replied to you, redhawk0 but I see I didn't, I'm sorry . So thanks a lot for your hint. (Better late than never, indeed.)
No problem...I don't take anything personal. Good luck...they are tricky to get the old one off sometimes...
Another method for old chip removal...clip all leads first...then desolder each pin using solder wick. Its sometimes easier than trying to pry the entire chip off at once.
redhawk _________________ The only stupid question....is the unasked one.
. So thanks a lot for your hint. (Better late than never, indeed.)