Toyota Harrier ASU60/ASU65 Oxygen Sensor Wiring Diagram

[Roland.O]

This OEM diagram gives full circuit paths, wire colours and connector pinouts for the D40 plug assembly. It gives the procedures needed to check heater circuit feed voltages, verify stable grounding paths and isolate wiring faults from sensor element failures. Fixing O2 sensor issues without following these procedures can lead to pinning errors which can damage the ECM.

Common questions that this diagram answers​

1. What is the pinout chart for the downstream oxygen sensor D40 connector on a Toyota Harrier ASU60/ASU65?
2. How do I test the oxygen sensor heater circuit resistance on a Toyota Harrier ASU60/ASU65?
3. What are the wire colours for the oxygen sensor harness on a Toyota Harrier 8AR-FTS engine?
4. How do you isolate an open wiring fault from a failing O2 sensor element when diagnosing emission codes for Harrier ASU60/ASU65?

How to access the diagram​

Click on the link below to access the complete OEM Manual, within it you will find the Oxygen Sensor Wiring Diagram. I have given the screenshot below to help you quickly navigate to the section where the diagram is located. Once you find it, you can then print or save it. Let me know if you face any challenges or have any questions and I will be happy to answer in the thread below. Please note that the year in the document is not the YOM but the document release date so it covers the entire model range. Also note the document applies to all countries where the model is sold Including Singapore, Australia, Malaysia, Kenya, UK, New Zealand, etc.