Mazda 3 Wiring Harness | eBay 2010-2011 Mazdaspeed 3 ONLY. Interior dashboard wiring harness. One broken wire from removal of interlock device. - The third level quality part. - The second level quality part. It is of average mile.. 2007 Mazda 3 OE Wiring Harnesses & Stereo Adapters — Mazda 3 2007, Factory Replacement Wiring Harness by Metra®, with OEM Radio Plug. For factory stereo. This high-quality Metra wiring harness is just what you need to replace your defective or aged factory wiring harness.