Charger doesn't work with just power and ground wires

[Claghorn]

Another weird item: The new Nexus 7 (mine, anyway) won't notice a charger being plugged into the USB port.

This is a strictly charge only cable, having only power and ground connections plugged into the dedicated charger gadget the cable came with. When I plug in any other device I have, they all say "Goody! Power! I'll start charging up now!" When I plug in the 2013 Nexus 7, it acts like nothing happened.

(It does charge fine with the charger and cable that came with it, as well as when I plug it into a computer).

 

[John Bean]

Short the two unused data pins together in the charger. The Nexus (like most other modern devices) needs to see that the USB source is capable of providing charge current, not just that 5V is present; shorting D+ to D- at the power source is all that's required to make it work, but you need a full USB cable to allow it to "see" the shorted data lines.

 

[Claghorn]

Apparently the charger is already setup right, it was just the cable. Just tried a real USB cable and it charges fine now.