how to fix P0135 code on Volkswagen Golf MK7 (2015-2019)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle battery to avoid electrical shock.
• Allow the engine to cool down to prevent burns.

2. Inspect and Repair Wiring

• Sub-steps:
  • Visually inspect the oxygen sensor wiring harness and connectors for signs of wear or damage.
  • If damage is found, repair or replace the affected wiring or connectors.
• Tools Required: Wire strippers, electrical tape, soldering iron (if needed).

3. Replace Oxygen Sensor

• Sub-steps:
  • Locate the upstream oxygen sensor (usually near the exhaust manifold).
  • Use an oxygen sensor socket to unscrew and remove the old sensor.
  • Apply anti-seize compound to the threads of the new sensor (not on the tip).
  • Install the new oxygen sensor and tighten it to the manufacturer's torque specifications (typically around 30 Nm).
• Tools Required: Oxygen sensor socket, torque wrench.

4. Reconnect Battery and Clear Codes

• Sub-steps:
  • Reconnect the vehicle battery terminals.
  • Use the OBD-II scanner to clear any stored codes from the engine control unit (ECU).
• Tools Required: OBD-II scanner.