Showing results for 
Search instead for 
Did you mean: 

Clock-Signal Repair Pictures ISR4300, ASA, ISR4400

Bernhard Roth


We have many devices affected by the clock-signal issues.

Cisco does replace the units with repaired/fixed ones.

I have received some ISR4321 routers with the fix applied (pictures attached).

The Cisco provided fix is of - well - mediocre quality (loose solder joints etc..) but works.

I am an EE engineer and am able to fix other routers of my customers as well (attached a picture of one of my fixes).

Spot the difference :)

Is there anyone which has received fixed ASA5506, ASA5508 and ISR4331 routers?

Please post pictures of your fix (hi-res if possible)

I ask because I would like to fix them as well (some of my customers) and avoid configuration, license etc. migration.

I am aware that I might void Ciscos warranty by this act of evil :)

Best regards,


84 Replies 84



is it possible to use a round carbon metal film or a round metal film resistor instead of a surface mount?

I need a temporary fix to get back my config file.



As long as the resistance value is right, any resistor will be ok.


It'll depend on your soldering skills, quality of the magnifying glass and whether you can physically get it soldered to the board......



I live in Montreal Canada and it was very difficult for me to get parts in a reasonable time because of the covid pandemic (Canada Post delay is 1 month when you order something online)...

I made it using an Arduino kit I bought for my kids a few year ago... no 150 ohms resistors in this kit but 1x100ohms + 5x10 omhs did the job, see picture attached.

I know it is ugly but it worked and I have my config file now, I don't recommend it, but if you don't mind to loose the router forever why not, it may help others in the same situation.