Posted: Sun Oct 09, 2016 9:01 Post subject: Belkin F5D8235-4 v2 (v2010ed)
Hi to all
I have been using this router for 3 years and it performed rock solid. Until yesterday. Yesterday he failed in curious way. Wifi portion of it is working and I can connect and access his web page (DHCP works and communication works) but LAN part is dead. If I try to connect with wired connection DHCP does not provide address. If I set manual IP in IP range of DHCP and router and try to ping it all fails. There is no response at all. My pc detects that there is network and that is it.
As far as i could figure out there is no communication between WIFI and LAN parts. If someone can help in reviving it I would appreciate it very much.
Oh and I have managed to return it to stock firmware and still no luck
I experienced similar problem with my F5D8235-4 v2 with LAN and WAN ports failed suddenly. Wifi was still working and I could use the router as repeater only. I believe the CPU couldn't communicate with the LAN switch IC anymore, i.e. a hardware failure. It lasted for another year, just used it occasionally for testing purpose, until it died recently, unit couldn't boot anymore. Did you do any setting changes recently that may caused the problem? If not, there is very high chance that it is a hardware failure.
no changes at all. i have concluded that this is hardware problem. I will try next week to re-flow the board using hot-air gun. i had previously re-flowed laptop mb with great success. i'm hoping that this is some case of bad solder joint.
will post the result
Solution is to use hot-air gun and to heat up RT3052F chip (smaller one).
This router is divided in two sections, first one is a regular switch with control option and other is WIFI section with everything else.
My problem was that switch section was not communicating with WIFI section. So there was no DHCP no real network and no communication with router over LAN.
I had presumed that problem was similar to graphics card problems on laptops. BGA chips are known for failing with broken solder joint, and this causes failure in communication.
It is the first time I hear that BGA bad soldering can be fixed by hot air gun. Anyway, good job, well done! What kind of hot air gun are you using? Can you post a picture? Can you also provide more details about the hot air gun settings like the temperature and how long did you blow at the chip and how far is the tip of the gun away from the chip surface? I am really excited to learn how you did that. Thanks in advance!
I replaced this exact model a few months ago after experiencing the same port failure you describe. At the time I assumed there was a voltage spike across the WAN that killed it, but a more reasonable explanation is that the BGA's solder failed.
It may be interesting to note that this router worked fine for over 4 years with one of Eko's custom builds of v23sp2, but 2 or 3 weeks before the port failure I updated it to the latest available build, for no particular reason. That was in mid-July. I spent a little time researching the issue before throwing the router in the trash, but I didn't keep track of exactly which build I had flashed.
I don't know if it's reasonable to draw a connection between "newer" builds of DD-WRT and hardware faults, or perhaps it was just coincidence, but I would advise others with this router not to update. _________________
@js1662 process was done without any measurement. it was all using educated guessing. I have watched at unpopulated places for components, if solder was moving (something like jelly) under hot air gun that was sign that i need to heat everything for minute or so. i was heating chip more using circular motion and every now and then i would pass over pcb close to chip. just to ensure that there is no huge difference between pcb and chip.
airflow was low and heat on medium to ensure that all small components stay in place.
I wish that i could be more exact but i have decided that i have nothing to loose.
@cetverooki, thank you so much for the information! I may give it a try to my dead router later when I have the mood and time. However, the hot air gun that I have has a tiny nozzle so it may not work as good for large components like the BGA chip.
