Parts for your 2015 Mitsubishi Asx-Temperature sensors

2015 Mitsubishi ASX temperature sensors — what they do and when to service them

Temperature sensors are absolutely used on the 2015 Mitsubishi ASX. Mitsubishi’s factory service and wiring manuals for the ASX/Outlander Sport/RVR (GA2W/GA3W series) document multiple temperature sensors: an Engine Coolant Temperature (ECT) sensor for the ECU and radiator fan control, an Intake Air Temperature (IAT) sensor (typically integrated in the MAF on petrol models), an ambient air temperature sensor for the HVAC/cluster, and on CVT-equipped vehicles a transmission fluid temperature sensor within the valve body. Diesel variants also use exhaust gas temperature (EGT) sensors to manage DPF regeneration. These are also reflected in MUT-III diagnostic procedures and OBD-II fault sets (for example P0115–P0119 ECT, P0113 IAT, P0070–P0073 ambient, and CVT fluid temp-related codes). So yes—temperature sensors are relevant, fitted, and critical to how a 2015 ASX runs.

On this model, temperature sensors help the ECU trim fuelling and ignition, decide when the cooling fans cut in, manage idle speed on cold starts, and keep the air-con behaving. In CVT models they protect the transmission by adjusting line pressure and shift strategy based on fluid temperature. Diesel ASX models rely on EGT sensors to control emissions and trigger DPF burn-offs safely.

As part of regular servicing, there’s no fixed replacement interval for these sensors—replace on condition. What pays off is preventative care:

• Keep the cooling system healthy: fresh, correct-spec coolant at the recommended interval, sound radiator cap, and no leaks. A crook cooling system can mislead a good ECT sensor.
• Inspect connectors under the bonnet, especially around the thermostat housing and MAF. Look for brittle plugs, green crust (corrosion), oil ingress, or chafed wiring.
• Scan for codes if there are hard starts, rough cold idle, poor fuel economy, a pegged temp gauge, or fans that run flat-out. ECT/IAT/ambient codes point you straight to the right sensor.

When replacing an ECT sensor, let the engine go stone cold, disconnect the battery, relieve pressure, and be ready to catch a small coolant loss. Swap the sealing washer if specified, torque to the workshop manual spec, refill with the correct coolant mix, and bleed the system. Clear any codes and check live-data on a scan tool—coolant and intake temps should be believable and track ambient when cold. Avoid silicone sealants on sensors, they can contaminate readings.

A quality OE-equivalent sensor and tidy wiring will keep a 2015 ASX running sweet, from chilly morning starts to summer highway stints, across Australia and New Zealand.

• Typical symptoms of a failing temp sensor: hard cold starts, high idle that won’t settle, sootier tailpipe on petrols, the temp gauge behaving oddly, fans running constantly or never starting, and higher fuel use.

FAQs

Where is the engine coolant temperature sensor on a 2015 ASX?
It’s usually threaded into the thermostat housing or cylinder head on the radiator side of the engine. On the 2.0L petrol it sits near the upper radiator hose area, on the diesel it’s similarly positioned but tighter to reach. Look for a two-pin plug, access is under the bonnet from the front/top with the engine cover off.

Do I need to bleed the cooling system after replacing the ECT sensor?
Yes. Top up with the correct coolant, set the heater to hot, run the engine at fast idle, and squeeze the upper hose to purge air. Top up as the level drops and fit the cap once the thermostat opens and the fan has cycled. Recheck the level after a short drive and again the next morning.

Can I drive with a faulty temperature sensor?
It’ll often run, but it’s not a good idea. The ECU may default to rich fuelling, the fans might misbehave, and on CVT or diesel models it can affect transmission strategy or DPF performance. It’s better to diagnose and fix promptly to avoid bigger bills.