broadband ut300r2u modem,link light stays on forever

[playit]

ut300r2u modem,link light stays on forever no matter if if dsl phone wire connected or not.i dint mess with any firmware ,it started to be like this for past few months until it stopped all together to work anymore,so learned that flashing might help, need dump file for this modem, i have only ch34a1 programmer.so i erased and flashed with few bin or ras files i got from internet but nothing worked.so further reading let me know that have to flash a whole full dump .if any idea, pls share, thank you.

[stj]

Re: broadband ut300r2u modem,link light stays on forever

from this thread:
https://www.routertech.org/viewtopic.php?t=3154

there is more than 1 board used with that name on the outside.
so find out which cpu/modem chip yours has first.
then we can look for the correct firmware

[playit]

Re: broadband ut300r2u modem,link light stays on forever

thank you for messaging. this is the chip 25X16VSIG winbond memory flash ,WINBOND/W9864G6GH-6, BCM6332KFBG broadcom chip.i cant go inside to see the bootloader or firmware version, but at back sticker i see v/n 21001697, i have found some D-Link DSL-2520U ADSL2 Ethernet/USB Combo Router uses kinda the same chip.. but not able to find out the whole dump.

[boyebaran]

Re: broadband ut300r2u modem,link light stays on forever

hi
please send clear picture of board-label and....
and check all important voltage on board like 3.3v -cpu voltage-adapter and...
also you can use hot air (a little) to check for any change (use backup of main dump first)
i sent dump of dsl-2520u z2-ver:1
please test

[playit]

Re: broadband ut300r2u modem,link light stays on forever

oh thank you sir, i will send all the pics now

[playit]

Re: broadband ut300r2u modem,link light stays on forever

i have saved a backup bin file from the modem i had ,but i took this backup after the modem went bad. the bin i saved as backup ,i cant attach it here.

[playit]

Re: broadband ut300r2u modem,link light stays on forever





i checked the voltages of WINBOND/W9864G6GH-6 they are all good ,those vdd ,vddq according to chip data. but i dont see how i can check volatages for this BCM6332KFBG broadcom chip,i also checked the j5 pins , ground pin is at top and others are 3..3 volts.

[playit]

Re: broadband ut300r2u modem,link light stays on forever

hi
please send clear picture of board-label and....
and check all important voltage on board like 3.3v -cpu voltage-adapter and...
also you can use hot air (a little) to check for any change (use backup of main dump first)
i sent dump of dsl-2520u z2-ver:1
please test

yes sir,i even hot gunned a little few 30-40 secs with flux liquid on the chips before erasing flashing chip,but still it was same result.the previous day to this happend , that night was heavy ligtening,nearby. my modem was already having connection problems. this was on feb 2022 - "he link light stays on when i switch on modem ,it usually flickers then stays on after getting stable -it just took like 15 secs ,but now a days.. when i switch on modem ,the power light is on, the link light (yellow with no flickering) is on , sometimes pc/usb light is off , this is where i would swtich it on and off till i get the pc usb light (green on and is stable , then the link line would flickr to get stable - finally connecting to internet -- all this time takes like 10 mins "

this is after a week - "after the line man fixed those wires , he said they are rusted so he cleaned it.. but the modem behaves the same way. when i swtiched it on the link line will be lit orange , the pc/usb light will blink on off , then i have restart power of modem again. then link line orange light will blink and get stable in few seconds , then it i get internet working. but i want to know why the modem is behaving like this now - "when i swtiched it on the link line will be lit orange , the pc/usb light will blink on off" . Before when i switch it on , the line link orange will blink few times and get stable, then pc./usb light would be stable already , then i get internet.. i need not restart the modem twice or thrice"

now "Jul 31, 2022" at night there was heavy lightening near by and still it was working whole night, then next day morning ,it worked a little , then suddenly , the lan stopped to connect,on off cycle. then dsl line kept solid lit no matter the dsl line connected or not.
today my ut300 gave up. the pc light keeps blinking, the phone line led is lit always no matter the phone line is attached or not. this happend suddenly. i tried testing some voltages in capacitors ,they showed near 5 v ( the adapter is 5v output) some capacitors showed around 3 v even after changing other capacitors.. ( i just did it to see if that would change anything..) but its the same behaviour. this modem lived for about 10+years on off use i guess. rip .. but i want to know the reason what caused this. or may be if possible repair it..

then i changed few capacitiors, still the result was the same, then i got to know flash might be corrupt somehow , so now trying to flash and see.i have only ch34a1 usb eeprom programmer.

[playit]

Re: broadband ut300r2u modem,link light stays on forever

here is the back up i made before doing any flashing.

[playit]

Re: broadband ut300r2u modem,link light stays on forever

hi
please send clear picture of board-label and....
and check all important voltage on board like 3.3v -cpu voltage-adapter and...
also you can use hot air (a little) to check for any change (use backup of main dump first)
i sent dump of dsl-2520u z2-ver:1
please test

i write this bin file, no change , also one leg of chip is shaking,, may be i breaking it i guess, but it reads in ch41a programmer.
now the ground pin of flash memory chip is broken completely but i managed to solder it to the board surface, this time the lan led stopped ,it just came for few seconds then it dint come, i tried resetting it,pressing reset button, then i saw the lan light coming up , then gone again, but no changes in dsl or power lights when i try resetting ,its all the same from before.

[playit]

Re: broadband ut300r2u modem,link light stays on forever

can anyone tell me how to use ch431a usb programmer in ttl mode serial , with this modem, i read that this supports ttl mode too.

[stj]

Re: broadband ut300r2u modem,link light stays on forever

is it the black pcb with gold plating?

[playit]

Re: broadband ut300r2u modem,link light stays on forever

if you asking about ch431a ,yes it is.

[boyebaran]

Re: broadband ut300r2u modem,link light stays on forever

pls change crystal oscillator of cpu.(with original bios) and test
seems that it is not bios problem .
if changing crystal no change you can resold cpu carefully

[playit]

Re: broadband ut300r2u modem,link light stays on forever

i managed to connect the ch341a to board, but no matter what speed i keep in putty it shows gibberish characters, no english. i dont have a original bios , i mean i dont have full dump , but i just took a back up from the chip ,i dont even know if the back up bin is good or bad i got to know what is crystal oscillator but i dont know which is cpu .. ? pls tell me what is cpu here in this board. the crystal oscillator number is h64j8p , i dont see that number in internet, which one should i get ? is it 16 Mhz-Crystal Oscillator ?

[stj]

Re: broadband ut300r2u modem,link light stays on forever

ch341
i have a schem and a chinese picture to help you work it out

on one side you have pins 1,2,3 & TXD,RXD,GND,5v

TXD,RXD & GND are your connections,
to use the board as a programmer you put the jumper between pins 1 & 2
to use the board as a serial interface you put the jumper between pins 2 & 3

[stj]

Re: broadband ut300r2u modem,link light stays on forever

cpu is the big square chip,
the crystal is next to the red and yellow leds

[boyebaran]

Re: broadband ut300r2u modem,link light stays on forever

i managed to connect the ch341a to board, but no matter what speed i keep in putty it shows gibberish characters, no english. i dont have a original bios , i mean i dont have full dump , but i just took a back up from the chip ,i dont even know if the back up bin is good or bad i got to know what is crystal oscillator but i dont know which is cpu .. ? pls tell me what is cpu here in this board. the crystal oscillator number is h64j8p , i dont see that number in internet, which one should i get ? is it 16 Mhz-Crystal Oscillator ?

my means you rewrite backup bios to 25q16.i said seems that this is not bios problem.

[playit]

Re: broadband ut300r2u modem,link light stays on forever

my means you rewrite backup bios to 25q16.i said seems that this is not bios problem.

ok ,i will get the oscillator chip , then will put the backup bios rewrite it on flash chip.but i dont know how to do this in serial mode , with putty i get grey boxes even in utf8 ,got to know that might be due to bad cable. i just connected with jumper wires badly, i dont have good fixation jumper wires ,will buy it too.yes sir,i acknowledge that, but i wanted to see what it shows in serial ch341a mode. so i tried it.but guess need good jumper cables for that.

[playit]

Re: broadband ut300r2u modem,link light stays on forever

ch341
i have a schem and a chinese picture to help you work it out

on one side you have pins 1,2,3 & TXD,RXD,GND,5v

TXD,RXD & GND are your connections,
to use the board as a programmer you put the jumper between pins 1 & 2
to use the board as a serial interface you put the jumper between pins 2 & 3

thank you ,i dont know chinese lol ,yes i managed to connect it in serial mode, but i am confused with tcx rxd pins in my board, its not written. i found the ground pin ,i connected only one ground pin and one supposedly rxd in board to txd in usb ,also i connect with other pin viceversa..still that grey boxes i see in putty. not sure which is which rxd or txd, in one forum one said if want to see just bootloader, connect gnd to gnd rx to tx in usb. so i tried it..but confused ,if touch any wire to pins in board ,i see a reading of greboxes then some letters ,i would have to buy jumper wires first to connect it well ,also oscillator. so the cpu is broadcom chip, it gets much hotter when i switch on modem for few secs.