The analog input connector should be connected with the red wire on analog input 0, and the back wires to ground.
The ground pins on the analog input connector are connected directly to the ECU ground plane. The ECU will be damaged if power is applied to these pins.
KPro3 (red) and KPro4 (white) analog input wiring
Early cables (sold until the end of 2011) have an orange wire.
Later cables (sold from the end of 2011) have a purple wire.
Kpro Analog Wiring from Hondata.com: http://www.hondata.com/help/kmanager/index.html?analog_wiring.htm