Parts for your 2009 Nissan Dualis-Temperature sensors

2009 Nissan Dualis temperature sensors — what they do and how to look after them

Temperature sensors are absolutely used on the 2009 Nissan Dualis (J10). Technical sources including the Nissan Qashqai/Dualis J10 Electronic Service Manual (EC: Engine Control System), the CVT/Transaxle manual (TM/CVT), and HVAC system documentation identify several temperature sensors: the engine coolant temperature (ECT) sensor, the intake air temperature (IAT) sensor, the CVT fluid temperature sensor, and the ambient air temperature sensor for climate control. Trade references like Autodata and Bosch Automotive Handbook also show these sensors in the vehicle’s control strategies and wiring diagrams.

On a 2009 Dualis, temperature sensors help the car run sweet as. The ECT sensor is the big one for engine management — it lets the ECU know how hot the engine is so it can sort cold starts, idle speed, ignition timing, and fuel delivery. The IAT sensor fine-tunes fuelling by reporting the air charge temp, which matters for performance and economy. If it’s got the Jatco CVT (common on Aussie/NZ cars), the transmission relies on a fluid temp sensor to manage line pressure and protect the unit when it’s working hard. Up front, the ambient temp sensor feeds the climate control so the cabin hits the set temp without fuss.

They’re not typically “service items”, but they do benefit from a bit of attention during routine servicing:

• Scan for codes and live data. Look at ECT and IAT readings stone cold and at operating temp, odd values point to sensor or wiring faults (common ECT codes: P0115–P0119).
• Keep connectors clean and secure. Green corrosion or loose pins can cause dodgy readings.
• Mind the cooling system. Fresh, correct Nissan-spec coolant and proper bleeding protect the ECT sensor and keep fans and the gauge behaving.

If the ECT sensor fails, symptoms include hard cold starts, rich running, high idle, the radiator fan stuck on, or a wonky temp gauge. Replacement on the MR20DE is a straightforward spanner job for a competent DIYer: let it cool fully, relieve any residual pressure, drain a little coolant, unplug the connector, swap the sensor and seal, then refill and bleed per the service manual. Tighten to the spec in the Nissan ESM — don’t overdo it. The IAT is often part of the MAF housing, clean the MAF with proper cleaner before condemning the IAT. The CVT fluid temp sensor lives inside the transmission and usually means valve body work — best left to a transmission specialist. As always, follow the owner’s manual for coolant change intervals and use the correct coolant to avoid dramas.

Popular questions

Where is the engine coolant temperature sensor on a 2009 Dualis?
On MR20DE petrol models, the ECT sensor is threaded into the engine near the thermostat housing, facing the radiator side. It’s accessible from the top with basic hand tools once intake plumbing is moved aside. Always work on a cold engine and catch any coolant spilled.

Do temperature sensors need regular replacement?
Not on a schedule. They’re replaced when faulty. Regular checks with a scan tool, clean electrical connections, and correct coolant changes go a long way. If readings don’t match reality (e.g., stone-cold engine showing 80°C), test the sensor and wiring before replacing.

What are common fault codes for Dualis temperature sensors?
For the ECT: P0115–P0119 range covers circuit and performance issues. IAT faults typically appear as P0110–P0114. CVT temp concerns can trigger transmission codes and limp mode. Always confirm with live data and wiring tests to avoid parts-darts.