[Samsung Epic 4G Touch] nivron:
This post is to describe the issues I've had with the USB Port in my E4GT. You may want to keep this thread handy in case it might help in the future.

This is software agnostic, so the kernel/ROM is not relevant.

So -- anywho -- yesterday I was out of town purchasing a new vehicle and noticed that my phone was getting really poor battery life. I generally can make it through a day with light usage, but I was getting serious, serious drain. I also had my first LOSs -- three of them within a hour. Since the beginning of October, I have only had one LOS, and that was a "ghost LOS". I think the LOS was obviously a major issue in the battery drain, but what I describe below could have had a serious effect as well.

I took the phone off overnight charge at 8:30 AM. After some discussions with the salesperson, he needed to do some stuff. I was waiting and reading a forum with xScope Pro (they didn't have Tapatalk). All of a sudden, Vlingo popped up and asked me to accept the license agreement. I cancelled out of that and the phone told me I was in car mode. I told it to deactivate car mode, and everything was okay. When I was using my EVO 4G, the forums were full of messages about car mode activating, but I never had that problem. I figured it was par for the course that one of my Androids would have this issue. By 4:30 PM, I had the car mode issue come up a few more times, but my car charger and my home charger worked fine.

This morning, my phone would not connect to the computer. I also had a strange "green screen" where everything was in a green hue on my phone. It apparently self-corrected about 10 seconds after it occurred. It would turn on the charging light, but not connect to the computer. My USB jig also did not function. It wouldn't turn the phone on. I started freaking out and was trying to prepare it to go back for a repair/replacement, but Odin wouldn't find it. I blew into the USB port to try to clear out any possible particles... That didn't help. I eventually jiggled/wiggled/cast magic and got it to Odin. Thinking it could be an issue with the kernel/ROM, I hoped that Odin back to stock would fix the problem. I did a ##RTN# reset and plugged it in. Absolutely nothing. No charging light, no beep from the phone or computer.

I started searching and found some XDA threads about the Int'l SGSII and apparently it is a known problem with these phones -- some people even replacing the USB ports themselves. I didn't look to see if the particular part was available for our phones, but I was able to solve the problem by the following:

Parts Required:

1. Dentek Floss Pick (or whatever is non-metallic and small)

2. Contact Cleaner (I didn't use this, but some people said it helped them)

My technique was to carefully use the toothpick to poke around in the USB port and flush out any particles that were in there. I didn't see anything come out. The interesting part of this was a suggestion to "bend the PCB down a bit". That's the part that sticks out of the USB port for your cable to seat on. I moved it down slightly (it doesn't seem to be terribly hard to move). Once I plugged the phone back in, everything worked again. My USB jig works, the regular charger works, the computer recognizes it. I plugged/unplugged it in many times after the "fix" and it seems to work!!

If you try this yourself, be careful not to damage the PCB in the USB port. I'm not responsible for anything that happens.

tl;dr version:

? USB port acting weird? Can't connect? Getting random car mode?

! Clean it out with contact cleaner/skinny toothpick

! Possibly bend the PCB down a smidge