Parts for your 2016 Toyota Vitz|yaris-Temperature sensors

2016 Toyota Vitz/Yaris temperature sensors – what they do and how to look after them

Temperature sensors are absolutely fitted to the 2016 Toyota Vitz/Yaris and they’re central to how the car runs. Toyota’s technical literature for the XP130 series (Repair Manual, New Car Features, and the Electrical Wiring Diagram) shows multiple temperature sensors on the 1.3‑litre and 1.5‑litre petrol engines, including the Engine Coolant Temperature (ECT) sensor, Intake Air Temperature (IAT) sensor (built into the MAF unit), ambient air temperature sensor for the A/C system, and transmission fluid temperature sensing on automatic variants. Toyota’s parts catalogues list these as serviceable components, and the diagnostics section of the repair manual references OBD‑II codes such as P0115–P0119 (ECT) and P0110–P0113 (IAT), confirming they’re very much in play on this model.

On this Yaris/Vitz, temperature sensors help the engine computer decide fuel mix and ignition timing, kick the radiator fans on and off, run the gauge properly, and keep the air‑conditioning working sweet as. A misreporting ECT can make cold starts grumpy, chew through more fuel, and keep the fans running when they don’t need to. A dodgy IAT can dull throttle response and bump up consumption. Ambient and evaporator sensors keep the cabin climate steady without you fiddling under the bonnet every weekend.

They don’t have a set replacement interval, but they do benefit from smart servicing. Try these easy wins:

• At each 10,000–15,000 km service, scan live data: cold ECT and IAT should roughly match outside temperature, warmed‑up ECT usually sits around thermostat spec.
• Check connectors for corrosion or broken tabs, fix poor grounds and brittle loom sections near heat.
• Keep coolant fresh (Toyota Super Long Life Coolant) and leaks sorted, air pockets can skew ECT readings.
• Clean the MAF/IAT with MAF‑safe cleaner only, never poke the sensing element.
• After front‑end repairs, confirm the ambient sensor in the grille is mounted correctly and not dangling.
• Auto trans fluid temperature sensing is internal, if shift quality or over‑temp codes appear, get a transmission specialist involved.

Replacing the ECT sensor is straightforward: cool the engine, relieve a little coolant, swap the sensor and new seal, then top up and bleed per the Toyota manual. Always torque to the spec in the service guide rather than “nip it up”. If you see codes like P0115/P0117 or the temp gauge acts weird, don’t ignore it—sorting a ,50–,150 sensor can save a radiator, head gasket, or a weekend roadside drama somewhere between towns.

Popular questions about 2016 Toyota Vitz/Yaris temperature sensors

Where is the engine coolant temperature sensor located?
The ECT sensor is typically threaded into the thermostat housing or cylinder head on the gearbox side of the engine, with a two‑pin connector. Exact placement varies slightly with the 1.3‑litre vs 1.5‑litre layouts, but it’s usually accessible from up top with the intake plumbing out of the way.

Look for a small brass‑coloured sensor body with a plastic plug, follow the upper radiator hose to the thermostat housing and you’re very close.

What are the signs a temperature sensor is failing?
Common clues include rough cold starts, higher fuel use, fans running constantly, a lazy temp gauge, A/C that cycles oddly, or a check‑engine light with codes like P0115–P0119 (ECT) or P0110–P0113 (IAT).

If live data shows impossible readings (for example, −40°C or 130°C on a cold start), suspect the sensor or its wiring before chasing bigger faults.

Do these sensors need routine replacement?
No scheduled replacement is listed in Toyota’s service info. They’re replaced on condition—when readings are out, faults are stored, or physical damage is seen.

Including a quick scan, connector check, and coolant health check in regular servicing is the best way to keep them happy for the long haul.