Parts for your 2007 Honda Fit-Temperature sensors

2007 Honda Fit (Jazz) temperature sensors — what they do and how to look after them

Temperature sensors absolutely are used on the 2007 Honda Fit (also known as the Jazz). Honda’s own 2007 Fit/Jazz Service Manual for the L15A engine details several temperature-sensing inputs used by the PGM‑FI engine management and climate systems, including the Engine Coolant Temperature (ECT) sensor (Cooling System and PGM‑FI sections), the Intake Air Temperature (IAT) sensor (PGM‑FI/Fuel & Emissions), and—on automatic/CVT models—a transmission fluid temperature sensor (Auto/ CVT transmission section). Models with outside temperature display or automatic climate control also employ an ambient air temperature sensor (Heating & A/C section). Aftermarket service databases (e.g., workshop platforms used in AU/NZ) list the same sensors for fault code diagnosis and servicing procedures.

On this model, the ECT sensor is the main player for warm‑up fuelling, ignition timing, idle speed control, radiator fan operation, the dash temperature gauge, and even engagement logic for i‑VTEC. The IAT sensor lets the ECU estimate air density, smoothing cold starts and helping optimise spark and fuelling across changing weather. Auto/CVT variants use transmission fluid temperature to adjust line pressure and shift scheduling, protecting the gearbox on steep climbs or in summer heat. If fitted, the ambient sensor informs A/C performance and the outside‑temp readout.

They’re tough little thermistors, but age, heat cycling, coolant contamination, and connector corrosion can throw them off. Common clues include hard cold starts, rich running or poor economy, a fan that runs constantly, an erratic temp gauge, lazy shifts (auto/CVT), or weak A/C at idle.

• Inspection: During routine servicing (every 40–60,000 kilometres), check the sensor connectors for green crusting, broken tabs, or oil/coolant wicking into the loom. Verify actual temperatures with a scan tool and compare to ambient.
• Locations: ECT lives near the thermostat housing/cylinder head under the bonnet, IAT is in the intake tract or integrated with the MAP assembly, the trans temp sensor may be inside the transmission or mounted on the case, the ambient sensor sits ahead of the condenser.
• Replacement tips: Use quality parts, a smear of the specified thread sealant if called for (never bundle on PTFE tape), and torque to spec. After an ECT swap, bleed the cooling system, top up with Honda Type 2 coolant, clear any DTCs, and perform an idle relearn if needed.

No fixed replacement interval is specified by Honda, treat temperature sensors as “inspect and test” items, replacing only when readings are out of spec or faults are logged.

Popular questions

How many temperature sensors does a 2007 Honda Fit have?
Most have at least two: the Engine Coolant Temperature (ECT) and Intake Air Temperature (IAT). Auto/CVT models add a transmission fluid temperature sensor, and trims with outside‑temp display or auto climate add an ambient air temperature sensor.

Exact fitment varies by market and trim, but these are all documented across the 2007 Fit/Jazz service manual sections for PGM‑FI, Cooling, Transmission, and HVAC.

Where is the engine coolant temperature (ECT) sensor on a 2007 Fit/Jazz?
It’s typically threaded into the cylinder head or thermostat housing area, facing the radiator side. Access is under the bonnet near the upper radiator hose.

Look for a two‑pin connector, confirm with a scan tool by watching coolant temperature change as the engine warms from cold.

Do temperature sensors need periodic replacement on the 2007 Fit?
No scheduled interval—Honda treats them as “service on condition”. If diagnostics show implausible readings, or there are drivability issues tied to temperature inputs, replacement is sensible.

During regular servicing, a quick visual check of connectors and a scan‑tool comparison to ambient temperature keeps trouble at bay.