Parts for your 2007 Honda Civic-Temperature sensors

2007 Honda Civic temperature sensors — what they do and how to look after them

Temperature sensors are absolutely fitted to the 2007 Honda Civic. Honda’s factory Service Manual for the 2006–2011 Civic identifies multiple temperature sensors, including the Engine Coolant Temperature (ECT) sensor and the Intake Air Temperature (IAT) sensor, with automatic models also using a transmission fluid temperature sensor. The manual’s Cooling System and Fuel & Emissions sections, plus Honda’s parts catalog (e.g., ECT sensor often listed as 37870‑RNA‑A01), and OBD‑II diagnostics (codes such as P0115–P0119 for ECT and P0112–P0113 for IAT) all confirm their use.

On a 2007 Civic—whether the 1.8‑litre or the 2.0‑litre—the ECT sensor feeds live coolant temperature data to the engine computer. That info steers fuelling, ignition timing, idle speed, VTEC engagement thresholds, radiator fan control, and the dash gauge. The IAT sensor helps fine‑tune mixture as outside and under‑bonnet temps change. If fitted, the transmission temperature sensor protects the auto by adjusting shift strategy when fluid is cold or hot.

There’s no routine replacement interval for these sensors, they’re service‑on‑condition parts. As part of regular servicing, a technician should scan live data to confirm the ECT tracks realistically from cold start to operating temp, compare IAT to ambient, and check for stored fault codes. Fresh Honda Type 2 coolant at the recommended interval helps keep the ECT reading accurately, because contaminated coolant can skew readings and corrode connectors.

• Common signs a sensor’s on the fritz: hard cold starts, rough idle, rich running or poor economy, cooling fans stuck on or never coming on, a dead or jumpy temp gauge, or a Check Engine Light with ECT/IAT codes.
• Replacement tips: let the engine cool completely, depressurise the system, and catch coolant. Use a quality OEM‑spec sensor, inspect the connector and wiring, and bleed the cooling system properly after refilling. Clear codes and verify with a scan tool that temperatures are reading sensibly and the fans cycle as expected. Avoid generic sealants that can affect sensor grounding—follow the Service Manual guidance and torque specs.

For autos, odd cold‑shift behaviour can point to a transmission temperature signal issue, but always confirm with live data and TCM codes before parts swapping. A quick electrical check can save a lot of guesswork.

Popular questions

Where is the engine coolant temperature sensor on a 2007 Honda Civic?
It’s mounted near the thermostat housing on the engine, with a two‑pin connector. On the 1.8‑litre it sits below the intake area at the housing, on the 2.0‑litre it’s similarly placed by the housing on the head side. Access can be tight—use care unplugging the connector.

Do temperature sensors need periodic replacement?
Not usually. They’re not a scheduled wear item. Replace only if testing shows bad readings, wiring damage, or relevant fault codes. Keeping the cooling system healthy and connectors clean goes a long way to ensuring long sensor life.

Can a faulty temperature sensor stop the radiator fans from working?
Yes. The PCM uses the ECT reading to command the fans. If the sensor reads wildly low or high, the fans may run constantly or not at all. That said, relays, fuses, fan motors, or a stuck thermostat can cause similar symptoms—diagnose before replacing parts.