The headphone jack on an iPhone 4S does not supply power. It has 3 contacts. It supplies left/right audio and a control signal and has a ground. It does not supply power in the "power supply" sense of the term. One cannot power other equipment from the headphone jack. It does supply a certain amount of power - audio power - measured in milliwatts, I believe. But that cannot be used to power another mp3 player (for instance) with operating power. But the audio signal can and will drive an amplifier that gets it's own operating power from it's own internal power supply.
There's alot of different techniques. I use a soft toothbrush and an electronic contact cleaner spray. The kind that leaves zero residue. Available at radio shack or over in the electronics section of lots of stores like Fry's. Got my last spray can at the auto parts store. Alcohol is a good substitute but zero residue contact/electronic spray can is The Right Thing. Using contact cleaner in a spray can works best because the spray pressure will chase water out of small components. The key to using a hair dryer or heat gun is to put it on low. Warm...low....no heat, just blow room temp....whatever your favorite tool has settings called like that. Low temperature is the key. I let it blow for a full day. Or many hours. Some people say no heat gun/ hairdryer because they're afraid you'll melt the solder or wire insulation and do additional damage. Well, I've got news for them. I use precision of judgment and I do not fry my delicate electronics under a 650 degree heat gun set on high. And I'll bet you can...
A quick search turns this up which looks promising. How can I fix my iPod Nano 6th Gen power button? There are also youtube videos about taking apart a nano 6g. A quick google turns up tons of info and parts.
Lose the $199.00. That way you can be sure. Saltwater is very very corrosive to copper circuit traces. The way I deal with saltwater is to immediately re-dunk the phone in fresh water and shake it out. And I do that a couple of times. Then the usual drying techniques. Was the lifecase defective? I'm wondering if I should stick with pelican for a waterproof case. Sorry for your loss.
Look inside the drive with a very bright flashlight and maybe a magnifier. If you're lucky you can retreive the sticky note that was left stuck on a CD. Inspect the ejected CD for scratch marks. Is the foreign object that is stuck in the drive actually scratching the CD? This can be a good indicator of whether or not the object is just a piece of paper or something more serious.
I definately agree. I use a stethescope to listen to the ipod and compare the sound against a known good ipod. Like oldturkey says....rhythmic clicking is a bad drive because there is only 1 moving part in any ipod....the drive platters and read/write heads. Normally, you can hear the platters spin...sounds like a whine. You can tell it's a spinning thing from the sound it makes. So if the sound is different - toast it is.
Inspect it very closely for any dings and scratches that might indicate an untoward impact. A repair shop would do that regardless of any statements to the contrary. Tether it to itunes and see if it shows up. Can you do an itunes restore? Does it appear to charge when hitched to itunes? Can you enable disk mode in itunes and get the ipod to show up on the computer desktop?
Does the same thing happen when it's tethered via the cable? If so, then it's prolly not the battery. If not, replace the battery. And if it's warranty then have apple deal with it. As usual, check your screen timeout settings and do a complete restore before you conclude that it's hosed.