Worked for me!
So, my WiFi on my iPhone 3g has not worked for ages. I understood it was not a software issue. I had proved this by doing the 'freezer trick' which made my WiFi work for a few minutes. Many times I have thought about how to repair it, but mainly been too woried about destroying my phone, so I've lived with it - until now! Found some information from Brad (SimpleServe) on YouTube and decided it was worth a try. In his YouTube video's description, there is many links to other users who have also gave this a try, so plenty of reading on others experiences is available.
Now as all the information on this is out there, I am just posting some photo's of my experience, and so far success at this fix.
I got myself an Oven Thermometer. I already own a Fluke IR non contact thermometer, which I have used for reflowing other parts in the past with a heat gun. The oven thermometer is a bit slow to react to temperature changes, so I found. By the time the oven thermometer reached 200°c, the actual temperature could be up to 220°c. This is where the IR non contact meter came in handy, as its readings are real time. Also, the temperatures inside the oven vary a lot depending on where I pointed the IR thermometer. Using both was handy. I concentrated on the temperature of the baking tray that was in the oven since I began to warm it up as it was a nice benchmark for temperature before inserting the logic board. Only problem with the IR thermometer is the need to open the door quickly to take a reading of the iPhone logic board or parts of the oven. Of course the logic board needs time to heat up to 196°c wen you put it in the preheated oven. All I know is that the last few mins, the actual iPhone logic board was at around 196°c as can be seen in the photo above. I took it out after 45 mins of cooling. The reason I never waited an hour is that it was down to room temperature by this time.
My smiley sucker friend for removing the screen!
Anyway, it worked for me. I cooked it with the EMI shield facing upward. I had the white component between the WiFi module and antenna socket resting on one of my foil standoffs as you can see in the pic. I done this as I read that someone tried reflowing this component only and it fixed their WiFi, so I thought it deserved special attention! It also helped gently push it against the board and stop it possibly dropping off all together. This is my worry as I attempted a reflow of a laptop motherboard part once and when I had finished, I noticed that the motherboard battery had dropped off the other side in the process, along with me melting some plastic parts!
Apart from all the information I provided here, I followed the instructions at the websites below.
Main article: http://www.iphonetiquicia.com/iphone-wifi-oven-trick/
YouTube video: http://www.youtube.com/watch?v=l1azZWWkmSg
iPhone disassembly video: http://www.youtube.com/watch?v=q2-L2kD--8M
Some photo's of my cooking session...
H A P P Y