hi mate this is a simple answere to this, you swap the red with the yellow, is to do with the power,
http://www.pioneer.eu/uk/support/manuals/AVIC-F900BT/index.html
download the AVIC-F900BT_installation_manual_EN_FR_DE_NL_IT_ES pdf
its on page 10 called connecting the power cord, hope this helped