Wiring a Powerlet socket to the unused OEM GPS power connector on the K1200S. Procedure will be similar for K1200R and K1200GT
Removal of the battery cover reveals this connector zip-tied in front of the battery.
This is the part you need to buy, to connect to the OEM plug hiding under the battery cover. BMW# 83300413585
The wires are numbered: #1 is ground, #3 is switched 12V. #2 is the speedo signal for the BMW navigator's dead reckoning feature. After tying off wire #2 (the speedo wire), this is the connector ready for spade plugs.
Here's the Powerlet socket installed in the battery cover. Take care to position the hole so that it doesn't foul underneath when mounted.
Another view of the socket.
Here's the wiring installed on the socket. I did go back and cover the positive connector with red shrink wrap. Just in case you were concerned.
Completed socket installation. Note label for dimwits like me who might think to plug in heated jackets.
Here's the socket with my tank bag plugged in. I'm currently running a Zumo 550 off the socket, along with my cell phone charger and radar detector.