GTrusted

The Apple 15" MacBook Pro (Late 2016) enjoys optimal USB Power Delivery charging using its own Apple 87W USB-C Power Adapter but the Mac does allow to be charged using certain non-Apple charging sources like the Targus 45W USB Type-C Laptop AC Wall Charger (click here for Amazon pricing).

The Targus 45W USB Type-C Laptop AC Wall Charger starts communicating over USB Power Delivery with the Apple 15" MacBook Pro (Late 2016)  by declaring its source capabilities of 15 watts (5 volts @ 3 amps), 36 watts (12 volts @ 3 amps), and 37.5 watts (15 volts @ 2.5 amps). For some reason, the Mac gets rejected by the charger when it requests to pull 37.5 watts (15 volts @ 2.5 amps).

The Mac again requests 37.5 watts (15 volts @ 2.5 amps) after a hard reset which the charger finally accepts.

Later on however the Mac strangely requests to draw 15 watts (5 volts @ 3 amps) which the charger also complies.

While the Apple 15" MacBook Pro (Late 2016) is being charged on an already well charged battery, oddly we see that the charger initially delivers about 37.5 watts (15 volts @ 2.5 amps), stops delivering power, delivers 30 watts (15 volts @ 2 amps), and then delivers 5 volts as the current pull drops to 0 amps.

We can confirm that the Targus 45W USB Type-C Laptop AC Wall Charger is unable to achieve a successful USB Power Delivery protocol negotiation with the Apple 15" MacBook Pro (Late 2016).