Hi, I was in need to replace my USB-A to lightning cable. With the gloom of everything switching to USB-C I was looking for some cheaper alternatives on Aliexpress.
To do my diligence I looked up all the brands on the official apple MFi page. I found a cable from a brand called "smartdevil". Their product page contained the normal Aliexpress fuss like using two control chips or a nylon band.
It also contained claims I deemed as valid. Like offering USB 2.0 transfer speeds of 480Mps or a list of fast charging capable devices.
These claims made me pull the trigger and I ordered two 1m long cables around 3$ each. For the first time ever I received them in smartdevil branded bubble wrap bags and not those generic bags. Every cable was individual boxed, shrink warped and had a printed on 16 digit number behind an "uncover to check for authenticity" sticker. The QR code contained the url "ck.fw-12365.com". Once I entered my 16 digit code to this page it confirmed a "genuine" product.
So far so good I thought. Unwrapping and unboxing the cables revealed that the lightning cable connector misses two pins on both sides. I started my research and found a 2y old reddit post. Comments reached from definitely not MFi or you won't be able to transfer any data.
To concur these claims I took my old iPhone 8 plus out of the drawer and connected it to an original Apple 12W USB-A charger. I used the trollstore app "nice battery" to check charging speed and compared them to my original apple cable. They both showed the same speed of around 1400mA at time of testing.
Next I did some research on what the missing pins might do. According to TechInsights and nyansatan they are data pins. I plugged my phone into my computer expecting it to not show up but wrong again. The phone asked for permission to share data with my pc and showed up. I was able to transfer photos over to my pc like with the original apple cable.
I'm now somehow confused. What are this missing pins supposed to do? Did Apple just include them for future expansion of lightning? Do they serve another purpose like communication of accessories which I don't need? Why would smartdevil put in the extra work with branded packaging and a verification website if they were fake? I hope someone can clear this up for me or can provide me with some thoughts.
If requested and I allowed by the mods I can share the aliexpress url but I don't want this to be removed because of advertisement.
TL;DR bought a lightning cable of aliexpress from a brand contained in the MFi database. Two pins are missing on the connector side. Charging and data transfer works like on my original apple cable. My research gave me no answer what the missing pins do. Please help.
I don't think the missing pin is a data pin - I think it might be a charge pin and possibly one that is only required for "fast" charging.
AFAIK a proper lightning cable can provide up to 30 watts, but way back in the early days of the cable the maximum was 5 watts and I wouldn't be surprised if there are physical differences in the wiring that separates those two speeds. There are probably other speeds in between those two as well.
... yeah that's only 7W. Like I said, lightning does up to 30W, though with an iPhone 8 the maximum is 12W (or 18W for an iPhone 8 Plus). So it seems my theory is correct, the missing pin is compromising charge speed.
You said you compared ti to an "original Apple cable"... but not all Apple cables have the same specs. The ones that charge faster are generally heavier and not as nice to use (also, more expensive).
Lighting is loosely based on USB (Apple was heavily involved in the USB-C cable/connector design process and working on it at the same time as they were inventing the Lightning cable. They seem to have done a lot of things the same in both - since they both had all the same requirements).
USB can operate with anywhere between 4 and (I think) 14 wires. And a lot of those extra wires are redundant, for example you can fight EM noise (interference from other nearby electrical devices) by sending the same data "inverted" at the same time across two cables running in parallel. If there's no interference, that doesn't gain you any performance at all, but if there is interference it could be the difference between a cable that works perfectly and a cable that doesn't work at all.
It's pretty common for cables to have pins that aren't being used - a USB-C cable with only 4 internal wires will have a lot more than 4 pins... so removing a pin is probably fine. However I'd question what else they also removed... some things are definitely not OK to remove from the cable and many of them can't be seen from the outside. You'd have to disassemble the cable or do a CT scan.
As far as I know, MFI certification involves sending sample cables to a third party company that will test the cable and make sure it's compliant.
Just because the cables they sent in for testing were complaint doesn't mean the one they sold you is compliant. In a country with strong consumer protections, you'd be entitled to a refund if someone sold you a non-compliant cable that they claimed was compliant.
Don't mess around with this stuff. People have literally been killed by unsafe phone chargers.
Totally agree with your concerns about the usb charging bricks. I only use genuine ones there. I did some further testing with original apple usb-c to lighning cables. Both 18W and 20W managed the same charging speed of around 1500-1600mA in my short test. Maybe I'm fine with only charging older model iPhone?