Lightning cables failing due to corrosion

Lightning cables failing due to corrosion

Summary: Two of the Lightning cables that came with new iPhones I purchased in September have failed and corrosion is clearly visible on the contacts.


About a month ago the Apple Lightning to USB cable (PN: MD818ZM/A, $19) that I keep in my vehicle for charging my iPhone 5s began to fail. At first charging was intermittent, then within a week the cable wouldn't charge my iPhone at all. A closer look at the male end of the Apple Lightning to USB cable reveals that several of the gold contacts have become corroded. 

My corroded Lightning cables - Jason O'Grady

A check of Apple's discussion forums reveals that other users have had issues with corroded lightning cables. Experiences with Apple support representatives vary, with some users being accused of liquid damage (which isn't covered by Apple's warranty) while others have had their cables replaced without issue. 

Apple Discussions user "brockap3" noticed that the corrosion is happening mainly on the VBUS/V++/Power providing pin of his Lightning cable (here's an image of the pinouts of the lightning connector). He offered two possible scenarios:

  1. Two gold electrodes placed in an aqueous solution with a positive voltage on one wire and ground applied to the other will corrode the positive gold electrode away
  2. Electrical arcing causing the corrosion (originally I dismissed this as it is just USB - i.e. 5 V /2 A max)

Brockap3 posted photos of the corrosion on his Lightning cable taken with a microscope:

Lightning cable corrosion 1 by Apple Discussions user brockap3 - Jason O'Grady
Photo: brockap3
Lightning cable corrosion 2 by Apple Discussions user brockap3 - Jason O'Grady
Photo: brockap3

In my case, both my wife and my Lightning cables failed due to corrosion within a month of each other. Both iPhones were purchased at launch (September 20, 2013) making them just over five months old. Luckily we purchased both iPhones with AppleCare+ and the Apple retail representative I spoke with by telephone recommended that I make an appointment to bring the cables in to the Genius bar. I'll update this post with the result of my visit. 

Update 2014-0305: Anecdotal evidence from reader emails indicate that these failures seem to be more prevalent in wet/moist climates and of cables kept in a vehicle. If the Lightning end of the cable is dropped onto/dipped into a wet or snowy floor mat (while plugged into a vehicle’s 12 volt power outlet) it can arc/short the cable (and even the device!) if plugged in while the end of the cable is still damp. My local Apple Store replaced both corroded Lightning cables, no questions asked (although both iPhones have AppleCare+). 

Have you had a corrosion issue with an Apple Lightning cable?

Topic: Apple

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  • Do you have a lot of humidity?

    haven't seen this myself (I have the lightning adapter on my iPod Touch 5G, and my daughter has the iPhone 5.)
    • Cords

      Problem with cords is that after several hundred times of plugging in and out it is bound to get dirty, bent, wet, or just break. I know lots of people that have iPhone cable issues, problem solved by paying Apple $20 for a new cord. I solved this issue by using Nokia Lumia wireless charging and will never go back to cords again.
      Sean Foley
      • yes I use wireless on the nexus.

        However, maybe its just the relatively cheap Qi charger I am using ($35) but its tough to find the sweet spot and it charges at like 600mA tops.
        I'd rather just plug in a charger and in a hour and a half max, its done,at double the rate, guaranteed.

        Plus using USB means cables are so cheap and laying around everywhere. The reversablity of the lightning connector for me does not solve any big problem, just adds expense.

        Its finding the hole in general, not the directionality. I have an iPad mini so I realized that.

        Also with wireless charging, its expensive to have more than one of those.

        Seems like everyone speaks good about wireless but I really haven't found it to be an advantage in reality. It has the potential to improve, though.
        • High output adapter needed

          I found using a Qi with my LG G2 didn't seem to work well either, but then I swapped the AC adapter with a higher output one (2000mA) and it works great. Full charge in little over an hour. It's just a bit easier than plugging in a cable, but if I want to grab the phone during the night, there's no connected tail to deal with. I'd spend the money on a Qi again.
      • yes, I would like to see Apple and others go wireless

        The less contact tech, the better.
      • Easily solved ? $20

        $20 for this cable is extortionate. Why should anyone pay for a cable if the product has not passed the device's guarantee period. After all the gold is lifting from the base metal and shows no blackening or salt to indicate corrosion. This indicates a manufacturing fault in the plating process. If you pay $20 for a grossly overpriced cable you will see the cable fail once more after 5 months unless it really WAS a manufacturing fault. Even if a baby sat there sucking the end of the cable you shouldn't get corrosion on the gold but you might see on the base metal.
  • Doesn't look like corrosion, looks like deposits.

    Gold is the most non-reactive metal, so it is difficult to believe that corrosion happened.

    From the microscope photos, it looks like something was deposited on the gold, perhaps a metal from whatever it was in contact with.
    • Deposits?

      It looks to me like the gold plating is peeling off. Something was not done right in the plating process. It could affect several batches, everything from one (Chinese) factory, or something in the specific formulation of the metals is not compatible.
    • Though it's less likely that the gold plating solution is contaminated

      it could be that the nickel plating (most commonly used with gold for it's adhesion and help in reducing mechanical wear of gold) is substandard, or maybe even the underlying copper pads are not up to spec.

      Any one can cause issue, but I agree, that actually looks like solder or melted tin plating from the mating surface of the other device, as corrosion is usually not that smooth or shiny.

      Could the connector be heating up, something it wasn't supposed to do?

      I'm checking the plug on the wife's iPad when I get home tonight :)
    • I would suggest pitting (from arcing)

      Microscope images are notoriously difficult to interpret and I would assume that few contributors use one regularly. There is confusion in the responses as to whether the features on the contacts are above or below the surface of the contact.

      If the images are lit from the upper left side, then the features are below the surface (see the bright regions to the lower right). If the object is lit from the lower right then the features stick up.
      It appears that the lighting is from the upper right, therefore the features show material removal from the contact faces.

      The features look consistent with electrical arcing causing pitting (not corrosion products or electrolysis) There are also some feint black marks on the white insulator part that would also suggest arcing products being deposited on the insulator region

      • It does not look like pitting

        Then again most pitting I see is with medium voltage contacts - 120/208v and 277/480v contactors - bit these pics look more like something was melted (for lack of a better term) on the contacts as opposed to pitting. Usually (again with medium voltage) there is some sort of carbon build up (black marks) and definite pits if it's arcing and pitting. I suspect that the low voltages with this would be similar.
    • Thin

      When the gold is as thin as on these cables it will get corroded when there is arcs from pluging and unplugging. Plus if the female connectors aren't gold (perhaps copper or brass), the two different metals coming in contact with electricity flowing through them will also cause corrosion. The only way around this is to have a thicker layer of gold on the contact points. The difference between 1 and 2 micro's can mean the difference between wear and corrosion. And you can just about bet that these cheap Chinese made cables have the thinnest gold contacts that they can get away with.
    • Yes why jump to corrision

      It looks like like resistance heating or arcing caused, the damage does not look like corrosion at all.
    • Exactly what I was going to say

      Some of that 'corrosion' is raised ABOVE the rest of the contact. It looks like someone dropped solder on it in my honest opinion.
  • Premium only refers to the price

    Not the quality. Apple makes cheap junk. You can get the same cheap junk for Android devices, but it just costs $3 instead of $19.
    • Proprietary

      Proprietary is always more expensive. Apple should have used standard USB or Qi wireless charging. Their decision to use proprietary cord did not have cost savings in mind. Apparently their is a tech reason for it which nobody knows about or uses.
      Sean Foley
      • Oh, I certainly get why they didn't go for standard USB

        Those jacks are really flaky. I broke the one on my PlayBook and had to get the fast charger.
        • not as big a problem

          If a USB cable goes bad, another one is dirt cheap. Go to
      • Its called money

        When you have a proprietary cable, like apple does. Apple get a license fee from every cable created. Where as the rest of the phones you can use any micro usb and the companies do not make as much.
    • Interesting that you say that

      Because I can put my iPhone 4S on eBay right now and it will fetch a much better price than any similar vintage or newer Android or WM device - with the exception of the latest releases. And my iPhone 4S has outlasted a similar vintage Android device I owned - an HTC Thunderbolt. And HTC is not cheaply made kit. Sorry but your fervent Android worship and iHate zealotry does not change the fact that Apple also makes decent kit and is of much better quality than the majority of the Android and WM offerings.