how to fix P0135 oxygen sensor code in Volkswagen Golf MK7 (2015-2019)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Raise the vehicle using a jack and secure it with jack stands if needed.

2. Inspect and Repair Wiring

• Tools Required: Wire strippers, electrical tape, multimeter.
• Instructions:
  1. Visually inspect the wiring harness for the upstream oxygen sensor.
  2. Repair any damaged wires by stripping the insulation back and splicing them with solder or wire connectors.
  3. Use electrical tape to insulate any exposed wires to prevent shorts.

3. Replace Oxygen Sensor

• Tools Required: O2 sensor socket, ratchet, torque wrench, penetrating oil.
• Parts Required: New upstream oxygen sensor.
• Instructions:
  1. Locate the upstream oxygen sensor on the exhaust manifold or front pipe.
  2. Apply penetrating oil to the sensor's threads and allow it to sit for a few minutes.
  3. Use the O2 sensor socket to unscrew the old sensor.
  4. Install the new oxygen sensor by screwing it in by hand and then tightening it to the manufacturer’s specified torque (typically around 30 Nm).
  5. Reconnect the electrical connector to the new sensor.

4. Reconnect Battery and Clear Codes

• Instructions:
  1. Reconnect the negative battery terminal.
  2. Use the OBD-II scanner to clear the P0135 code from the vehicle's computer.