2005 Toyota P0118: What It Means & Is It Safe to Drive?
P0118 on the 2005 Toyota: Engine Coolant Temperature Circuit High Input. Here's what it means, what usually causes it, what repairs typically cost, and whether it's safe to keep driving.
What this code means
The engine coolant temperature (ECT) sensor is reporting a voltage signal that is too high, which the PCM interprets as an extremely cold or open-circuit condition. This is opposite to P0117 (low input) and often means the sensor or its wiring has failed open.
Common causes on the 2005 Toyota
- Failed engine coolant temperature sensor
- Open circuit in ECT sensor wiring
- Corroded or damaged sensor connector
- Low coolant level exposing the sensor
Symptoms
- Check Engine Light
- Engine runs rich (PCM thinks it is always cold)
- Poor fuel economy
- Hard starting when warm
Typical fixes
- Replace engine coolant temperature sensor
- Inspect and repair wiring and connector
- Check coolant level
Repair cost range
For a 2005 Toyota, repairs for P0118 typically fall between $50 and $200, depending on the root cause and labor rates in your area.
Known issues on Toyota
Toyota P0118 typically means the coolant temperature sensor has failed open circuit or its wiring connector is corroded. On 2AZ-FE engines, the ECT sensor is on the thermostat housing—inspect the connector pins for corrosion before replacing the sensor.
Most commonly affected models