P0115moderate severityPowertrain
Engine Coolant Temperature (ECT) Sensor 1 Circuit
on 2024 Hyundai Nexo Hydrogen Fuel Cell · FWD
What this code means
General malfunction in the engine coolant temperature sensor circuit.
Symptoms
- Check Engine Light
- Poor fuel economy
- Hard starting
- Incorrect temp gauge reading
- Fans not operating correctly
Common causes
- Faulty ECT sensor
- Wiring damage
- Corroded connector
- Low coolant level
Diagnostic steps
- Test ECT resistance at known temperature
- Inspect wiring
- Check coolant level
- Compare ECT to IAT at cold start
Repair notes
Replace ECT sensor or repair wiring. Verify coolant level.
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Other Powertrain codes on this vehicle
P0070
Ambient Air Temperature Sensor Circuit
P0071
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P0072
Ambient Air Temperature Sensor Circuit Low
P0073
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P0116
ECT Sensor 1 Circuit Range/Performance
P0117
ECT Sensor 1 Circuit Low Input
P0118
ECT Sensor 1 Circuit High Input
P0119
ECT Sensor 1 Circuit Intermittent
P0125
Insufficient Coolant Temperature for Closed Loop Fuel Control
P0128
Coolant Thermostat Below Regulating Temperature