Parts for your 2005 Mitsubishi Pajero-Temperature sensors

2005 Mitsubishi Pajero temperature sensors: what they do and when to replace them

Temperature sensors absolutely are fitted to the 2005 Mitsubishi Pajero. Factory literature for the NM/NP series (2000–2006) details an Engine Coolant Temperature (ECT) sensor on both the 3.2L 4M41 diesel and the V6 petrol engines, plus an Intake Air Temperature (IAT) sensor, and an automatic transmission fluid temperature sensor on V5A51 autos. These are also reflected in OBD‑II diagnostics with codes such as P0115–P0119 for ECT and P0110–P0114 for IAT, as listed in Mitsubishi service manuals and common workshop references.

On this Pajero, temperature sensors let the ECU and other control units make smart, real‑time decisions. The ECT sensor reports how hot the coolant is so the ECU can adjust fuelling, ignition, idle speed, glow‑plug timing on the diesel, and kick radiator fans on under the bonnet. The IAT sensor helps trim mixtures for Aussie and Kiwi climate swings. Auto models use transmission temp to protect the box, while the HVAC system relies on ambient and evaporator sensors to keep cabin temps comfortable.

If a sensor goes out of spec, owners may notice hard cold starts, rough idle, high fuel use, lazy throttle response, or the temp gauge and A/C behaving oddly. The check‑engine lamp and stored fault codes are common giveaways.

During servicing, it pays to check live data with a scan tool: coolant temp should plausibly track from ambient to operating range (about 80–95°C) as the Pajero warms up. Inspect connectors for corrosion, cracked housings, or coolant leaks around the ECT boss. On the 4M41, the ECT sits near the thermostat housing, on V6 petrols it’s on the intake manifold water passage. Replacement is straightforward: cool the engine, depressurise the system, drain a little coolant, swap the sensor with a new sealing washer, torque to spec, refill and bleed.

Handy tips:

• Use OEM or quality aftermarket NTC sensors, mismatched resistance curves cause drivability issues.
• Renew old coolant to prevent sensor fouling and electrolysis.
• After replacement, clear codes and verify warm‑up behaviour, fan operation, and thermostat opening with a scan graph.
• For autos that tow or see beach work, monitor trans temp data and keep the cooler clean.
• Test thermostats.

Popular questions about 2005 Mitsubishi Pajero temperature sensors

Where is the engine coolant temperature (ECT) sensor on a 2005 Pajero?
On the 3.2 Di‑D (4M41), it’s mounted near the thermostat housing on the front of the engine. On the V6 petrol, look on the intake manifold’s water passage. It has a two‑pin plug. Always confirm by matching the connector and sensor profile before removal.

What are the signs a Pajero temperature sensor has failed?
Cold‑start struggles, rich running, poor fuel economy, radiator fans stuck on, odd temperature gauge behaviour, or an illuminated check‑engine lamp are classic. A scan tool showing implausible readings (for example, 130°C on a cold start) is the clincher.

Do I need to bleed the cooling system after replacing the ECT sensor?
Yes. You’ll usually lose a small amount of coolant, so refill with the correct spec and bleed air out. Warm the engine with the heater on, top up as the thermostat opens, and confirm stable operating temperature on a scan tool.