Questions & Answers for Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter

I have a 13-inch 2018 MacBook Pro, the Thunderbolt 3 to Thunderbolt 2 adapter allows me to connect to the thunderbolt display, and the graphics are working fine.

The USB ports also functioned without a problem.

Updated:

To get the ethernet on the display working, I had to disconnect the USB-C adapter, delete (AFAIR) the Thunderbolt Bridge from the network preferences, and then reconnect the adapter.

• Answered by Patrick M from Portland
• 16/08/2018
• Flag as inappropriate Answer (can i connect my new 2018 macbook pro to my 2012 thunderbolt display)

Yes you can, according to Apple support document HT207266 "About the Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter".

It says "You can also use the Thunderbolt port of this adapter to connect an external hard drive, dock, Mac, or other device that uses a Thunderbolt or Thunderbolt 2 cable for data transfer. This adapter supports data-transfer speeds up to 10Gbps with Thunderbolt devices, and up to 20Gbps with Thunderbolt 2 devices.

This adapter is bidirectional, which means you can use it to connect Thunderbolt 3 devices to a Mac that has a Thunderbolt or Thunderbolt 2 port. In that case, the Mac must be using macOS Sierra or later, and the device using Thunderbolt 3 (USB-C) must provide its own power."

• Answered by Joseph V from Fort Langley
• 17/08/2018
• Flag as inappropriate Answer (Can i use this cable to transfer data from a 2014 MacBook air 11 inch to a 2018 MacBook 12-inch? I tried the migration wirelessly but did not work.)

I have tested with a 2015 MacBook Pro (Thunderbolt 2) running El Capitan connected to an AKiTiO Thunder3 Duo Pro (Thunderbolt 3) and it worked.

• Answered by Joseph V from Fort Langley
• 19/12/2016
• Flag as inappropriate Answer (Can I use this adapter to connect a thunderbolt 3 device (i.e. TB3 external hard drive) to a Mac Pro that has Thunderbolt 2 ports?)

No (except read below). The Thunderbolt 3 to Thunderbolt 2 adapter is only for Thunderbolt devices.

The LG 27UK850 is not a Thunderbolt display. It has 3 inputs: HDMI, DisplayPort, and USB-C with DisplayPort alt mode (not Thunderbolt).

The USB-C port of the LG 27UK850 cannot be used to power the MacBook Pro 2015. It can be used to power the MacBook or a MacBook Pro 2016 or later (but only provides 60W where the MacBook Pro might consume more during heavy usage).

For video output to the display, the simplest connection to your MacBook Pro 2015 to the LG 27UK850 can be done with a Mini DisplayPort to DisplayPort cable (not included). To use the USB downstream ports of the display (for keyboard or mouse or thumb drive or whatever you like), you need to connect a USB-C to USB-A cable (not included). The downstream ports will work as USB 3.0 (5Gbps) in this configuration.

There is a way to get video over USB-C to the LG 27UK850 from the MacBook Pro 2015. Connect a Thunderbolt 3 device that has two Thunderbolt 3 ports (such as a Thunderbolt 3 dock or RAID drive) to the MacBook Pro 2015 using the Apple Thunderbolt 3 to Thunderbolt 2 adapter. The second Thunderbolt 3 port of the Thunderbolt 3 device can be used to connect a USB-C cable to the LG 27UK850 for video and USB data.

Note that if you're using USB-C for video, then the downstream USB ports of the LG 27UK850 can only work as USB 2.0 (480 Mbps). This is because a 4K 60Hz display requires all four super-speed lines of the USB-C cable for the DisplayPort signal.

• Answered by Joseph V from Fort Langley
• 23/04/2018
• Flag as inappropriate Answer (Will this adapter allow me to connect an LG 27UK850 monitor (with USB-C) to my MacBook Pro (13", Early 2015) using a Thunderbolt 2 cable?)

Yes, you can, according to Apple support document HT207266 "Connect devices and displays with the Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter".

However, this is only useful for Thunderbolt networking (read Apple support document HT206909 "Networking two Mac systems directly with a Thunderbolt 3 cable requires Thunderbolt-enabled hosts") and Target Disk Mode (read Apple support document HT201462 "Use target disk mode to share files between two Mac computers").

The 2017 iMac does not support Target Display Mode (read Apple support document HT204592 "Use your iMac as a display with Target Display Mode") so you cannot use the 2017 iMac as a display for the MacBook Pro.

• Answered by Joseph V from Fort Langley
• 13/12/2017
• Flag as inappropriate Answer (does this work for connecting a 2015 macbook pro 13 retina to a 2017 5k imac?)

Connect the Apollo's Thunderbolt 2 cable into the Thunderbolt port on this adapter. Then connect the USB-C port of the adapter into the iMac's USB-C port. Easy Peasy.

• Answered by Patrick O
• 20/03/2018
• Flag as inappropriate Answer (Will this work for connecting my Universal Audio Apollo Twin MKII Audio Interface (Thunderbolt 2) Along with a USB-C cable, to my 2017 iMac?)

I can confirm this adapter will not power the new MacBook Pro's. However all the usb and ethernet ports functionality works.

• Answered by Ryan S from Thompson's Station
• 16/11/2016
• Flag as inappropriate Answer (With this adapter can I connect an Apple Thunderbolt Display to a new MacBook Pro (USB-C) and power the laptop through the same connection?)