Fix Your Stuff Community Store

Fourth generation iPhone. Repair is straightforward, but the front glass and LCD must be replaced as a unit. GSM / 8, 16, or 32 GB capacity / Model A1332 / Black and White. This page aims to help users troubleshoot, fix, and seek help for the iPhone 4.

2397 Questions View all

Options

Logic board corrosion fix not working?

I was given an iPhone 4 from my friend, of whom said that he had the phone in his pocket during his swim practice for a solid hour. He said I could have it if I could fix it. So, I gave it a shot and tried some stuff I read about.

He had given me a new battery replacement, so I would just need to fix the LGB. There was some obvious corrosion taking place, so I scrubbed it with 91% isopropyl and waited, then to reflow it, I stuck it in the oven at 200F for 7 minutes, and let it cool in there for an hour.

I'm probably just beating a dead horse here, but the phone still won't work. I'd like to know if it's not permanently broken, and if there's some sort of workaround.

Answer this question I have this problem too

Is this a good question?

Yes No
Score -1
Add a comment

2 Answers

Filter by:
Most Helpful Newest Oldest
Most Helpful Answer

Options

Well who knows. A 200F is certainly not going to help since solder doesn't flow at temps that low. Even so, you have to manually scrub off the oxidation at the corroded solder joints with an iron (in my experience.)

Your phone will work if you systematically replace all of the corroded/damaged/missing components using a donor board. This can quickly go down the rabbit hole though, since sometimes the parts that need replacing are practically impossible to transfer.

best of luck.

Was this answer helpful?

Yes No
Score 2

2 Comments:

Ah, thanks. Might as well make a last stand, though- what temperature would you recommend I use? I've seen many posts online about reflowing this board using low heat, and a lot that have older model phone boards but use heat up to 400F.

by

An oven reflow isn't the right tool for the job here. I just wrote a very similar answer. Try reading this: Knocked some tiny chips off, tips on what they are?

by

Add a comment

Options

I wouldn't recommend reflow in an oven - you might be damaging the plastic parts/connectors

You should have worked backwards from where you thought the problem originated.

Try searching for a schematic and test the board to see what you can do.

If not - look for a super sonic cleaning service. It will do what a toothbrush cant and remove corrosion from underneath the BGA chips

Check the board and make sure you didnt remove any components as well while cleaning/heating

Was this answer helpful?

Yes No
Score 1
Add a comment

Add your answer

Zetta McHallogen will be eternally grateful.
View Statistics:

Past 24 Hours: 0

Past 7 Days: 0

Past 30 Days: 0

All Time: 105