iPhone Wi-Fi Not Working? Time to turn up the HEAT! Attempting the Oven Reflow Fix in the BreakTryCatch Test Kitchen Sunil


I own a 1.5 year old iPhone 3G. A few weeks after upgrading to iOS 4.0.1, I lost Wi-Fi connectivity. I could go into Settings>Wi-Fi and see my wireless networks but after entering my password I would get a dialogue saying the password was invalid. I tried Settings>General>Reset>Reset Network Settings, restoring my iPhone from backup and restoring as a new iPhone. I also reverted back to iOS 3.1.2 thinking it might be an operating system issue, but still no Wi-Fi.

These are the official Apple troubling shooting guides for Wi-Fi networks and connections:



A friend of mine had similar Wi-Fi issues with her iPhone 3G after upgrading to iOS4. She had her handset replaced at a Apple Genius Bar, in spite of it being out of warranty and over two years old. I thought I would tried my luck too, but after visiting three different Apple Stores, none of the Geniuses wanted to give me a replacement handset. I’m not sure what the store policy is on replacement handsets, but maybe you have to catch a Genius on a good day! I was told my best option would be to update to an iPhone 4, which at the time of writing this post, is next to impossible to find in Toronto, Canada.

I did a little more research and found a 140 page thread on the Apple discussion forums with iPhone 3G users having Wi-Fi problems!!!


Clearly my situation was not unique, and this is a known issue with the Wi-Fi chips in these phones.

Flaky Wi-Fi can be caused by weak soldering connections on the iPhone printed circuit board (PCB). These soldering connections can develop cracks over time.

One of the more interesting fixes to solve this issue comes from Brad (SimpleServe) on YouTube. It’s a hardware hack that involves baking your iPhone PCB in a conventional oven at 385F for seven minutes, to re-solder the Wi-Fi chip connections on the board. Baking the board on your kitchen oven mimics the actual production process for the PCB, where it is passed through a reflow oven to solder the chips onto the board.

Since I had followed the official troubleshooting guidelines, my phone was out of warranty and I couldn’t get a replacement I had nothing to lose.

The cooking instructions and background info from Brad (SimpleServe) can be found here:



Brad also has a new repair method that is safer using a heat gun:


Here are some photos from my baking experience plus some tips for others out there that are willing to give this fix a try.

Most dismantling tutorials recommend using a plastic tool called a spudger to pry the screen up from the bezel. I tried using a spudger, but couldn’t find enough clearance to pry the screen up without damaging the bezel.

A much easier way to remove the screen without scratching the screen or bezel is with a suction cup.

Screen separated from bottom casing.

PCB still fastened to bottom casing.

Use a Phillips #00 Screwdriver. My hack was almost scuttled very early on, because I stripped the heads off two screws fastening the PCB to the back case. I ended up using 3 different screwdrivers, before I found one that was the right size. There are 8 screws fastening the PCB to the bottom case. The screw heads are soft and appear to use some type of adhesive on the threads.

PCB removed from iPhone.

Most dismantling tutorials don’t mention removing the camera module from the PCB. If you bake your board with the camera module still attached I’m pretty sure you’ll melt the camera!

These are the chips responsible for Wi-Fi.

PCB elevated on foil racks to prevent excessive heat radiating from the tray and oven rack.

Baking the PCB!!

Bake for 7 mins at 385 F, then let cool for 1 hr on the oven rack. Don’t touch PCB while it is cooling.

Look Wi-Fi is back! I’ve read that sometimes it takes a couple reflows in order to get stable Wi-Fi. I will continue to update this post as I put the phone through it’s paces….

Update – Oct. 5, 2010

Wi-Fi failed on  my iPhone, two weeks after the bake. I reflowed again, this time with the heat shield down and Wi-Fi has returned.

Update – Oct. 16, 2010

Wi-Fi is remains stable on phone, after downloading several gigs of data…

Why stop now?…Does your iPhone randomly vibrate with a flickering mute icon on screen? Even more DIY fixes for random vibration…

After fixing the Wi-Fi and feeling more confident about taking the phone apart and putting back together, I tackled another problem with my iPhone, where the phone would randomly vibrate due to a faulty mute switch. I replaced the exterior toggle switch (link) AND iPhone 3G headphone cable jack  assembly (link) which contains volume, power, headphone and mute switch. Also while the phone was undergoing surgery I decided to replace the battery (link).

I ordered these iPhone 3G parts from http://www.idemigods.com/

Replacing the headphone jack assembly is difficult, because it requires transferring the existing vibrator, metal backing, and silent/ring switch assembly. I destroyed the original headphone jack assembly when removing the parts that I had to transfer over to the new jack assembly.

There is double sided tape that fastens the ribbon to parts of the back case and jack, that you need to replace. When I re-assembled the phone the vibrate switch was working, but the headphone jack only worked through one channel when I plugged in my headphones. I fixed my original issue, only to cause a brand new, more annoying problem! Initially I had omitted replacing the original double sided tape, so it’s possible there may have been a short or a loose connector. I disassembled the phone, and retraced each step  and replaced the double sided tape where necessary and the second time around the head phone jack work perfectly.


iPhone 3G Disassembly:


Headphone Jack, Vibration Switch, Volume and Power:


Battery Replacement:


This entry was posted on Monday, October 18th, 2010 at 7:27 am and is filed under iPhone. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.