Audi Oxygen Sensor Replacement with Pictures Jul 24, 2019Connect the oxygen sensor wire harness by plugging it in. If you are using a universal oxygen sensor you will need to use the diagram that came with the sensor to find out which wires to splice. The typical cost to change the Audi oxygen sensor yourself is less than $100.Author: YOUCANIC VWVortex - HELP! O2 sensor wiring diagram! Apr 10, 2019Red/Wht is the other heater wire for sensor #1. Red/Yel is the other heater wire for sensor #2. Gry & Blu wires are the 2 sensor wires for #1. Vio & Red wires are the 2 sensor wires for #2. These wire codes are for the connector that plugs into the O2 sensor itself. The wiring colors for the sensors itself are: Wht & Wht are the heater wires.