Engine Water Temperature Sensor 1
This code indicates a fault with Engine Water Temperature Sensor 1.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The Engine Control Module (ECM) uses a sensor to monitor the engine's coolant temperature. If the temperature reading is out of a normal range, the ECM triggers this code to alert you.
What the computer is actually seeing
The ECM expects the coolant temperature to be between 190°F and 220°F (approximately 88°C to 104°C) during normal operation. If the signal voltage from the sensor is below 0.5V or above 4.5V, it triggers this fault code.
What a healthy reading looks like
Normal voltage from the coolant temperature sensor should be between 0.5V (cold) and 4.5V (hot) corresponding to the coolant temperature range of approximately 32°F to 248°F (0°C to 120°C).
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the engine coolant level: Ensure it's above the minimum level.
- 22. Inspect the wiring and connectors for Engine Water Temperature Sensor 1: Look for damage or corrosion.
- 33. Use a multimeter to measure the voltage from the sensor: Should be between 0.5V to 4.5V while the engine is at operating temperature.
- 44. If the voltage readings are out of the expected range, replace the engine coolant temperature sensor.
- 55. If voltage is normal, check for short circuits or ground issues in the wiring harness.
Common causes
- Faulty Engine Water Temperature Sensor 1
- Wiring issues or damaged connectors to the sensor
- Coolant leaks affecting temperature readings
- ECM software issues or failure
Typical repair cost
$$
Related codes
Frequently asked questions
Can I drive the vehicle with this code?
Yes, but be cautious as it may lead to overheating issues.
Will this fault code come back?
If the sensor or wiring issue isn't fixed, it will likely return.
Why does this code appear with other codes?
Multiple codes can indicate issues with the engine monitoring systems or related sensors.
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