Parts for your 2016 Lexus Is-Temperature sensors

2016 Lexus IS temperature sensors — what they do, care tips, and FAQs

Temperature sensors are absolutely fitted and highly relevant on the 2016 Lexus IS range. Factory technical sources — including the Lexus/Toyota service manual and wiring diagrams (TIS), New Car Features manuals for the 8AR‑FTS, 2GR‑FSE and IS300h drivetrains, and the OBD‑II diagnostics covering ECT, IAT, ambient and evaporator sensors — all document their use across engine, transmission and climate systems. You’ll typically find an engine coolant temperature (ECT) sensor, intake air temperature (IAT) sensor, ambient/outside temp sensor, A/C evaporator and cabin temp sensors, and a transmission fluid temp sensor (plus HV battery temp sensors on IS300h).

These sensors let the car think for itself. The ECT guides fuelling, ignition timing, VVT‑i operation and radiator fan control, keeping the engine happy from a cold Kiwi morning to a scorching Aussie arvo. The IAT fine‑tunes load and spark to suit air density. Ambient and evaporator sensors help the climate control cool quickly without icing the evaporator, while the cabin sensor keeps the temperature comfy. Transmission fluid temperature steers shift feel and protection, especially on hot days or steep climbs. When any of these go out of whack, the car may default to rich mixtures, run the fans constantly, shift oddly, or deliver ordinary A/C performance.

• Quick service tips: Inspect connectors for green crust, moisture or broken locks. Check harness routing near hot exhaust or sharp edges. Keep coolant fresh and correct (no tap water under the bonnet). After any cooling system work, bleed air properly so the ECT reads true.
• Diagnosis beats guessing: A scan tool showing live data is gold. Compare ECT and IAT when stone‑cold — they should match ambient. Look for implausible spikes, stuck values, or slow response as the engine warms.
• Replacement approach: There’s no fixed interval, replace on fault or drift. Use quality OEM‑equivalent parts, new O‑rings/gaskets, and torque to spec from the workshop manual. For IS300h HV battery temp issues, leave it to trained hybrid techs.

• Signs it’s time to test or replace: hard cold starts, high idle, poor fuel economy, temp gauge misbehaviour, radiator fans running full‑tilt, lazy A/C, harsh or delayed shifts, or stored codes like P0115–P0119 (ECT) and P0110–P0114 (IAT).

Look after the sensors and the IS rewards you with smooth manners, tidy fuel use and long component life — just what owners on both sides of the Tasman expect.

How many temperature sensors does a 2016 Lexus IS have?
It depends on the variant. All have an engine coolant temperature (ECT) and intake air temperature (IAT) sensor, plus ambient/outside temp and A/C evaporator/cabin sensors. Autos add a transmission fluid temp sensor. The IS300h also monitors hybrid battery temperature.

Do temperature sensors need regular replacement?
There’s no scheduled interval. They’re replaced when testing shows they’re out of spec, contaminated, slow to respond, or causing fault codes. Regular checks of live data during servicing help catch drift before it becomes a headache.

Can the car be driven with a faulty ECT sensor?
It might still run, but it can over‑fuel, kick the fans on constantly, and mask real overheating. Prolonged driving risks poor economy and potential engine harm. Best to get it scanned and sorted promptly.