Fixing Cisco Linksys E4200 v2 Stability Issues

I have an old Cisco Linksys E4200 v2 and have decided to share my fix for various stability issues that are present in the hardware design. It’s still quite a useful little router for my purposes (even though now there are newer faster designs).

There are two problems that I have encountered:

  • Power Supply: The stock power supply is not the best and mine stopped working (the device would not power on after a year or two). The fix here is pretty easy, change the power supply.
  • Overheating / stability: There are a lot of reports of the E4200 overheating and becoming unstable. That is, after a couple of minutes or hours of functioning, it stops working.

My post deals mostly with the overheating issue.  A solution that I have found is to use a Raspberry PI heatsink kit to replace the heatpads and RF shield combo on the router. Other methods of freezing the router are not going to be long term solutions.

In order to install this, you need to open the router. There are screws on the bottom, hidden by plastic feet covers. There are then a set of plastic clips that hold the lid onto the router. Once open, the circuit board should look like the photo below.

There are two steps to the installation:

  • Install CPU Heatsinks: There are three RF shields. The two at the bottom are for wireless circuits and the larger one on the top is for the main CPU. Use a screwdriver to gently prise open the RF cover over the main CPU (it should click out). Take off the heat pads from the processors / surface mounted chips. Stick on the Raspberry PI chips as shown in my photo.
  • Create cooling vents: In order for the router to cool itself via convection, you need to add some cooling vents in the top cover. I recommend drilling holes into it in a grid pattern. You should cover not only the CPU area but also the wireless circuits as they are large generators of heat. Sure, it ain’t pretty, but it works.

Put the router back together and reboot it – it should start working.  Mine has been on for the past few weeks with some large sustained activity uploading to my AWS Glacier cold storage… and it works perfectly fine. Good luck!