Parts for your 2015 Ford Mondeo-Temperature sensors

2015 Ford Mondeo temperature sensors — what they do and how to look after them

Temperature sensors are absolutely used on the 2015 Ford Mondeo. Ford’s own Workshop Manual for the 2015 Mondeo (CD391), plus common data sources used in Aussie and Kiwi workshops like Autodata and Bosch ESI, list multiple temperature sensors on these cars: engine coolant temperature (ECT), intake air temperature (IAT, often integrated with the MAF/MAP), ambient air temperature for the HVAC, and—depending on engine—exhaust gas temperature (EGT) sensors for DPF control on the 2.0 TDCi, and transmission fluid temperature where applicable. Ford wiring diagrams and service procedures detail their roles in engine management, cooling fan control, A/C performance and, on diesels, DPF regeneration strategy.

On a 2015 Mondeo, these sensors are the quiet achievers. The ECT keeps the ECU honest about warm-up, ignition timing, fuelling and when to spin the radiator fans. The IAT helps trim mixtures on hot days up north and crisp mornings down south. Ambient temp keeps the climate control behaving, and the diesel’s EGT sensors protect the turbo and manage DPF burn-offs. If one goes out of whack, the car can chew more fuel, idle rough, run the fans constantly, or tip up a check engine light.

There’s no set replacement interval in Ford schedules, but they’re worth a check every service. A quick scan-tool look at live data from cold start to operating temp shows whether readings are believable. Visuals matter too: under the bonnet, inspect connectors for corrosion, brittle looms, and oil or coolant wicking into plugs. Use the specified Ford coolant and don’t mix types—poor coolant can foul ECT readings. If replacing a sensor, stick with quality OEM-spec parts, seal only as per the manual (some sensors are dry-seal, others need a specific washer), and on refitting an ECT, bleed the cooling system properly to avoid air pockets.

• Common symptoms of a failing temp sensor: hard cold starts, rich running, cooling fans always on, A/C performance issues, DPF regen faults (diesel), and fault codes like P0115–P0119 (ECT) or P00xx (IAT/charge temp).
• Handy tips: verify earths, compare scan data to an external thermometer when cold, and on diesel EGT sensors use anti-seize rated for high temps and torque to spec.
• No special “calibration” is normally needed—clear codes, road test, and re-check live data. Some ECUs may benefit from an adaptive reset via a scan tool after major sensor changes.

Where is the engine coolant temperature (ECT) sensor on a 2015 Mondeo?

On most 1.5/2.0 EcoBoost engines, the ECT is mounted near the thermostat housing or coolant outlet at the cylinder head. On the 2.0 TDCi, it’s similarly located around the housing area. Exact spot varies by engine code, so a quick look at the Ford workshop diagram or a torch under the bonnet near the top radiator hose usually finds it.

What are the tell-tale signs of a dodgy temperature sensor?

Expect poor cold starting, higher fuel use, fans running when the engine’s not hot, sluggish performance, or the A/C acting oddly. A scan tool reading that doesn’t match ambient temperature after an overnight sit is a big clue. The ECU will often log a fault code when the reading is implausible.

Do temperature sensors need coding after replacement?

Generally, no. These are resistance-based sensors and the ECU adapts automatically. After fitting, clear any stored codes, warm the engine, and confirm live data looks sensible. If other parts were replaced or the battery was disconnected, performing an ECU adaptive reset with a scan tool can help the car settle quicker.