Parts for your 2017 Honda Odyssey-Temperature sensors

2017 Honda Odyssey temperature sensors — purpose, care, and replacement

Based on technical sources including the Honda Odyssey 2014–2017 Service Manual (Cooling System, Fuel & Emissions, A/T Sensors, and HVAC sections), Honda OEM wiring diagrams, and the Honda parts catalogue for the 3.5L J35 V6, the 2017 Honda Odyssey is fitted with multiple temperature sensors. These include the engine coolant temperature (ECT) sensor, intake air temperature (IAT) sensor, automatic transmission fluid temperature (ATF/TFT) sensor, ambient air temperature sensor, and an A/C evaporator/cabin thermistor used by the climate control. So temperature sensors are absolutely relevant on this model.

These sensors help the Odyssey’s control modules keep everything running sweet-as:

• ECT: Feeds the PCM so it can manage cold starts, fuelling, ignition timing, radiator fan operation, and the dash gauge.
• IAT: Lets the engine management adjust mixture for hot or chilly intake air.
• ATF/TFT: Guides shift timing and line pressure to protect the 6‑speed auto when hot or towing.
• Ambient: Tells the climate control and instrument cluster the outside temp, affects A/C logic.
• Evaporator/cabin thermistor: Prevents evaporator freeze‑up and stabilises cabin comfort.

They’re not a routine “service item”, but a few smart checks during servicing keep them reliable. Inspect connectors for corrosion or broken locks, especially around the front bumper (ambient sensor) and under the bonnet near the thermostat housing (ECT). Keep coolant fresh to Honda’s schedule using the correct Honda Type 2 coolant, old or contaminated coolant can attack the ECT sensor and threads. Make sure intake plumbing and the air filter are clean so the IAT reads true. If the A/C seems erratic, the evaporator sensor or its harness near the HVAC case may need a look.

Warning signs of a crook temperature sensor include hard cold starts, black smoke or poor fuel economy, fans running flat‑out, erratic temp gauge, harsh shifting, weak A/C, or the MIL on with codes like P0116–P0119 (ECT), P0128 (thermostat performance), P0112/P0113 (IAT), P0072/P0073 (ambient), or P0711 (ATF temp). Replacement is generally straightforward for ECT, IAT, ambient, and evaporator sensors: disconnect battery, unplug, swap like‑for‑like, and torque as specified. Bleed the cooling system after ECT replacement. The ATF temperature sensor is typically internal to the transmission’s solenoid/harness assembly and is best handled by a professional. Stick with genuine or high‑quality aftermarket parts that match the original connector and resistance curve to avoid dodgy readings.

Popular questions

Where is the engine coolant temperature sensor on a 2017 Odyssey?
The ECT sensor is mounted near the thermostat/water outlet on the J35 V6, under the plastic engine cover at the front bank. It’s accessible from the top with the engine cold, expect a small coolant loss if swapping it out.

Can a bad temperature sensor cause overheating or fan issues?
Yes, a failed ECT can make the fans run constantly or not at all and can throw off fuelling. True overheating is more often due to low coolant, leaks, a sticking thermostat, or a blocked radiator, so diagnose the whole cooling system, not just the sensor.

Do temperature sensors need regular replacement?
No set interval. Replace only when faulty or damaged. During scheduled coolant changes and front‑end inspections, check connectors and wiring, especially the ambient sensor behind the grille which can be knocked about by road debris.