Kitz Forum

Broadband Related => Broadband Hardware => Topic started by: routerbox on October 05, 2021, 12:05:58 PM

Title: HG635, Bricked. power light only on
Post by: routerbox on October 05, 2021, 12:05:58 PM
Hi
All
Hope everyone is have a great time.
I need some help please

I have a HG635 router that has randomly bricked itself
I have tried resetting it several times and keeping the rest button pressed in for a long time but no lights flash
I am only left with the power light on.
The wireless does not work

I have connected the router to My laptop by ethernet cable by static IP
When i go to the router IP i get a page asking for the firmware image
I read here that there is an open source firmware that i downloaded and used the image file
HG635v1.04t_multicast_with_multicfg_pack.bin
It flashed it and the broadband light flashed, rebooted but got to the same page asking for a firmware update

Please can someone help me fix this
I am new to the router moding scene

Thanks so much in advance
Title: Re: HG365, Bricked. power light only on
Post by: Alex Atkin UK on October 05, 2021, 07:36:45 PM
Hmmm, that's not a good sign, I wonder if the flash memory has failed.  I know I had a router years ago that did the same and flashing the firmware did fix it.

Have you tried a couple of times to see if it will stick?  Unfortunately without opening it up and using a serial connection I don't think we can see if its triggering an error when flashing the firmware.
Title: Re: HG635, Bricked. power light only on
Post by: tubaman on October 06, 2021, 08:22:10 AM
The HG635 (assume this is what you have from the firmware you mentioned?) is a old TalkTalk device, but was one of their better ones.
If it successfully flashed the open source firmware but still fails then it does unfortunately sound like it might be terminal.
 :(
Title: Re: HG365, Bricked. power light only on
Post by: Jaggies on October 06, 2021, 09:56:00 AM
The old BT Business Gateways were notorious for failing power supplies, and the symptoms are much as described - only power light on. If you have a matching power supply from another device, try a swap.
Bear in mind the polarity, output voltage and current need to be the same.
Title: Re: HG365, Bricked. power light only on
Post by: routerbox on October 06, 2021, 11:50:14 AM
Hmmm, that's not a good sign, I wonder if the flash memory has failed.  I know I had a router years ago that did the same and flashing the firmware did fix it.

Have you tried a couple of times to see if it will stick?  Unfortunately without opening it up and using a serial connection I don't think we can see if its triggering an error when flashing the firmware.

Hi
Thanks for the reply
I did  try a few times but did no luck
I have it open
can i connect a uart adapter to this ?
Title: Re: HG365, Bricked. power light only on
Post by: routerbox on October 06, 2021, 11:52:12 AM
The HG635 (assume this is what you have from the firmware you mentioned?) is a old TalkTalk device, but was one of their better ones.
If it successfully flashed the open source firmware but still fails then it does unfortunately sound like it might be terminal.
 :(

Hi
Yes it is HG635,  corrected the mistake

[Moderator edited to insert the correct quotation.]
Title: Re: HG365, Bricked. power light only on
Post by: routerbox on October 06, 2021, 12:26:21 PM
The old BT Business Gateways were notorious for failing power supplies, and the symptoms are much as described - only power light on. If you have a matching power supply from another device, try a swap.
Bear in mind the polarity, output voltage and current need to be the same.

I have tried with another power supply but same thing

[Moderator edited to insert the correct quotation.]
Title: Re: HG635, Bricked. power light only on
Post by: Alex Atkin UK on October 06, 2021, 08:49:31 PM
I have tried with another power supply but same thing

[Moderator edited to insert the correct quotation.]

As in tried flashing using that PSU?
Title: Re: HG635, Bricked. power light only on
Post by: routerbox on October 07, 2021, 12:40:16 PM
As in tried flashing using that PSU?

Yes. did not make a diffirence
The broadband light does flash when being programmed and when it reboots the 192.168.1.1 webpage goes to the upload page asking for the firmware image
Title: Re: HG635, Bricked. power light only on
Post by: Alex Atkin UK on October 07, 2021, 10:13:14 PM
Only other thing I can think of is check any capacitors on the routers PCB.  I had to replace them on my ECI, haven't checked the HG612.
Title: Re: HG635, Bricked. power light only on
Post by: routerbox on October 08, 2021, 12:02:28 PM
Only other thing I can think of is check any capacitors on the routers PCB.  I had to replace them on my ECI, haven't checked the HG612.
I checked the caps
Dont see any bulging caps

Can I JTAG into this model
Title: Re: HG635, Bricked. power light only on
Post by: burakkucat on October 08, 2021, 01:19:01 PM
Can I JTAG into this model

Are the header pins (or the unpopulated solder pads) present on the PCB? If yes then "yes" is the answer to your question!
Title: Re: HG635, Bricked. power light only on
Post by: routerbox on October 08, 2021, 03:45:16 PM
Are the header pins (or the unpopulated solder pads) present on the PCB? If yes then "yes" is the answer to your question!

Thanks for the reply
Cant see any header pins or pads
some have said on the forum that this has been locked down
Title: Re: HG635, Bricked. power light only on
Post by: burakkucat on October 08, 2021, 03:59:54 PM
Cant see any header pins or pads

That is unfortunate. I can't think of any other way of recovering the device.  :(

[Edited to correct a typo.]
Title: Re: HG635, Bricked. power light only on
Post by: mofa2020 on October 08, 2021, 07:32:59 PM
On openwrt this router is stated as a NO JTAG connection available but serial is available although on the 2 pics of router's PCB I can not find any obvious serial connector.

https://openwrt.org/toh/huawei/hg635
Title: Re: HG635, Bricked. power light only on
Post by: burakkucat on October 08, 2021, 10:03:48 PM
Looking at the OpenWrt Wiki page for the Huawei HG635 (https://openwrt.org/toh/huawei/hg635) I see that it states --

How to connect to the Serial Port of this specific device:

Serial port settings 115200, 8N1

Pinout:
J5002
1 - RXD
2 -
3 - Probably VCC (3V3)
4 - GND
5 - TXD

After a careful examination of the image of the PCB, I found the location of J5002.  :)  See the image attached below.
Title: Re: HG635, Bricked. power light only on
Post by: routerbox on October 09, 2021, 12:19:28 PM
Looking at the OpenWrt Wiki page for the Huawei HG635 (https://openwrt.org/toh/huawei/hg635) I see that it states --

How to connect to the Serial Port of this specific device:

Serial port settings 115200, 8N1

Pinout:
J5002
1 - RXD
2 -
3 - Probably VCC (3V3)
4 - GND
5 - TXD

After a careful examination of the image of the PCB, I found the location of J5002.  :)  See the image attached below.

Hi Thanks for the image
and pinout
Can someone post a tutorial how to uart into the router
I Believe hyper terminal is used

Can i use this mode to flash the firmware or fix it so that it will accept the new firmware
Thanks everyone for the help so far
Amazing talent and forum
Title: Re: HG635, Bricked. power light only on
Post by: routerbox on October 11, 2021, 12:47:03 PM
I have an update all
What is really weird
I mean really weird as there is no other weird

I went to plug in the router using same power supply and lights flashed and everything was working
It was left unplugged on the shelf and i thought to myself
well i will give it one more try.

Definitely strange
Like the program twister strange
Title: Re: HG635, Bricked. power light only on
Post by: Weaver on October 11, 2021, 01:41:24 PM
I wonder if there is a cracked PCB track, and cooling it down a lot, by leaving it off for a long long time, will lower the temperature and cause things to contract and could cause a crack to close - highly speculative. If/when it fails again, try blasting its innards with freeze-it spray - that would be an interesting experiment. But anyway, sounds knackered in that case.

Actually, if you flip the board over, can you see any bad soldering? assuming there are some things that are non-surface-mount.
Title: Re: HG635, Bricked. power light only on
Post by: routerbox on October 11, 2021, 04:30:49 PM
I wonder if there is a cracked PCB track, and cooling it down a lot, by leaving it off for a long long time, will lower the temperature and cause things to contract and could cause a crack to close - highly speculative. If/when it fails again, try blasting its innards with freeze-it spray - that would be an interesting experiment. But anyway, sounds knackered in that case.

Actually, if you flip the board over, can you see any bad soldering? assuming there are some things that are non-surface-mount.

checked the board
maybe the flash took its time
hehhe