CONTROL ASSY-COOLANT TEMPERATURE

Engine Coolant Temperature Control Unit ️

This precision ECT sensor assembly keeps your Hyundai and Kia engine at the right temperature. It feeds real-time heat data to the ECU so the cooling fan, fuel mixture, and ignition timing stay correct. Smooth starts, steady idle, and clean emissions all depend on this small but vital part.

Why this part is needed

The ECU must know coolant temperature to enrich fuel when cold, switch the radiator fan, and manage thermostat logic. Accurate readings improve fuel economy, power, and catalyst life. It also prevents overheating in traffic or during towing.

How it works ⚙️

Inside is an NTC thermistor. As coolant gets hotter, resistance drops. The ECU reads the voltage change and calculates temperature. It then adjusts fan speed, air-fuel ratio, idle speed, and transmission shift strategy.

What happens if it fails

Common symptoms: hard cold starts, rough idle, high fuel use, black smoke, fan stuck on or off, and Check Engine light (codes P0115–P0119). Inaccurate data can cause overheating, gasket damage, or limp mode. Replace at first signs to protect the engine.

Tech tips for install

Work on a cool engine, relieve pressure, and top up with correct coolant after replacement. Inspect the 2-pin connector for corrosion, seat the O-ring, and torque to spec. Bleed air, clear codes, and verify live data with a scan tool.

Compatibility

• Santa Fe 20
• Sonata 19