I have maybe 20 cords that are like this because they would stop working and i would... lick them... to fix them! But after that they break and are like this! Ive tried tons of common ways to fix this like soaking them in vinegar, using rubbing alcohol, and using a pencil eraser! But nothing i try works! Please tell me a way to fix this!
How to lick your Problem
One thing led to another.
First, some terminology
What you are holding is an Apple Lightning™ connector.
Each little line on the end of the connector is a pin which connects a specific corresponding terminal in the Apple iPhone jack to a USB Power Adapter (the smooth white "lump-of-soap" that you actually plug into the wall power receptacle).
Second, some electrical theory
The pins themselves don't work (probably) because they appear to be corroded.
Moisture (your spit, or any liquid you may commonly find) conducts electricity. That explains why licking the connector tip "worked." Most any liquid would have "worked."
Pins must be completely dry or they will form a connection with the incorrect terminal in the receptacle. This causes a "short-circuit."
Counting from the left, pin #1 is the ground and pin #5 is the power.
Normally, a short-circuit involving power causes heat which may explain the plastic around the pins becoming darkened—some combustion has already occurred.
Third, some logic
When something unwanted happens and two parts are involved, repeatedly looking at only one as the cause of the issue is not productive. Here, one part is the USB to Lightning cable connector and the second is the iPhone jack itself.
Fourth, a warning.
Whatever else you do, if it involves using a liquid, allow the parts to completely dry before you plug-in anything that involves electricity.
A cellphone has enough electricity to explode and burn. The USB Power Adapter is connected to the power supply in your building hundreds of times more powerful than your cellphone.
That there was insufficient combustion for a fire is reason for thanks.
- The blackening of the connector is a symptom not the problem.
- Removing the blackening is treating the cosmetic (superficial) cable appearance not the reason for the appearance of the cable and the malfunction of the USB Power Adapter.
- The corresponding pins in your phone must look similar (bad) to the connectors on your Lightning to USB cable that you show in the photo.
- Replacing just the cable again will ultimately add to your collection of bad cables.
- Taking the iPhone in for repairs to the Lightning™ connector jack ($$$$) appears to be the solution to your problem. You'll also be advised (probably) to get a new Lightning to USB cable ($) at the same time.
Use something mildly abrasive, like 1200 grit emery paper, to clean them up. Whoever told you to use a pencil eraser should have been explicit that it should be an eraser intended for removing pen ink (mild abrasive, destroys the surface of the paper) not a pencil eraser (a soft rubber that envelops the graphite particles as it lifts them off the page, but doesn't abrade the page)