2008 Scion xD OE Wiring Harnesses & Stereo Adapters wwwd››Scion›xDScion xD 2008, Wiring Harness by Metra®, with OEM Radio and Speakers Plugs. For factory stereo. This high-quality Metra wiring harness is just what you need to replace your defective or aged factory wiring harness. 2008 Scion xD Hitch Wiring | Harnesses, Adapters, Connectors wwwd››Trailer Hitches›Hitch Wiring›Scion›xDScion xD 2008, T-Connector 3-Wire System with Converter by CURT®. For Models without Tow Plug, 3-wire System, Location: P3/P4. This provides all you need to connect a trailer to the tow vehicle.