Parts for your 2022 Toyota C-hr-Oxygen sensor

2022 Toyota C‑HR oxygen sensor: what it does and how to look after it

Technical sources confirm the 2022 Toyota C‑HR is fitted with oxygen‑sensing hardware. The Toyota Repair Manual for the C‑HR (AX10/AX50 series, 2022) specifies an Air‑Fuel Ratio (A/F) Sensor as Bank 1 Sensor 1 and a Heated Oxygen Sensor (HO2S) as Bank 1 Sensor 2 on its petrol and hybrid variants. The Toyota Electronic Parts Catalogue lists the corresponding DENSO wideband A/F and downstream O2 sensors. Regulatory frameworks such as Australian Design Rule 79/04 (Euro 5/6 aligned) and OBD‑II requirements (SAE J1979/ISO 15031) also necessitate upstream and downstream sensors for closed‑loop fuelling and catalytic converter monitoring on vehicles like the 2022 C‑HR.

On this model, the upstream wideband A/F sensor continuously measures oxygen content in the exhaust so the engine control module can fine‑tune the air‑fuel mixture. That keeps fuel economy sharp, drivability smooth, and emissions low. The downstream heated O2 sensor sits after the catalytic converter and checks how well the cat is cleaning up the exhaust. If the cat isn’t performing or a sensor drifts out of range, the system will log a fault and switch on the check engine light.

There’s no fixed replacement interval in Toyota’s schedule for these sensors, but they are wear items. Ageing, contamination (coolant or oil vapour), silicone sealants, or exhaust leaks can slow response times and bump up fuel use. Many techs consider proactive replacement of the upstream A/F sensor somewhere around the 160,000–200,000 km mark if fuel economy has slipped or scan data shows lazy switching, while the downstream sensor is usually replaced when it triggers a fault or catalyst monitoring issue. Always diagnose first: scan for codes (e.g., P0136–P0139, P0131–P0135, P0420), check live data, and inspect for leaks ahead of the sensor.

• Use an O2 sensor socket and penetrate threads on a warm (not hot) exhaust to avoid damage.
• Fit quality, correct‑spec sensors (Toyota/DENSO) with the supplied crush washer, torque to the service‑manual spec.
• Avoid anti‑seize unless the sensor maker pre‑applies it—many do. Excess can affect grounding and readings.
• Keep the loom off hot surfaces, don’t twist the lead when installing.
• After replacement, clear codes, verify closed‑loop operation, and confirm catalyst monitor readiness.

Look after the oxygen sensors and the 2022 C‑HR will reward with better fuel economy, cleaner tailpipe emissions, and a smooth, fuss‑free drive.

How many oxygen sensors does a 2022 Toyota C‑HR have?
The C‑HR typically has two on its petrol and hybrid variants: a wideband Air‑Fuel Ratio sensor (Bank 1 Sensor 1) before the catalytic converter and a heated oxygen sensor (Bank 1 Sensor 2) after it. Being a four‑cylinder with a single exhaust bank, there’s just the one pair.

When should the oxygen sensor be replaced?
There’s no set kilometre interval, but replace if fault codes or poor fuel economy appear, or scan data shows slow response. Many owners consider an upstream A/F sensor refresh around 160,000–200,000 km as preventative maintenance, with the downstream sensor replaced on condition.

Can it be driven with a faulty oxygen sensor?
Short trips are usually possible, but fuel use can rise and the catalytic converter may be at risk if the mixture goes rich. It’s best to diagnose and sort it promptly to protect the cat and keep the C‑HR running efficiently.