Engine Coolant Temperature (ECT) Sensor Circuit High
The engine's coolant temperature sensor circuit is reporting a high voltage condition.
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What it means (plain English)
The coolant temperature sensor is telling the computer that the engine is hotter than it really is, which can happen if the sensor is faulty or there's a wiring issue.
What the computer is actually seeing
The engine control module sees a voltage higher than 4.8 volts from the ECT sensor signal wire when it should be between 0.5 to 4.5 volts during normal operation, indicating a possible short to power or a malfunctioning sensor.
What a healthy reading looks like
ECT sensor should show between -40°F (-40°C) and 248°F (120°C) with a resistance range of 2,500 ohms at 75°F (24°C) dropping to about 25 ohms at 248°F (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 wiring harness and connectors for damage, corrosion, or loose connections. Look for shorts or frays that might cause high voltage readings.
- 22. Measure the voltage at the ECT sensor connector with the key on and the engine off. Voltage should be between 4.8 to 5.2 volts. If it's too high, suspect a short.
- 33. Disconnect the ECT sensor. With the sensor unplugged, measure the voltage from the connector. If it's still high, the issue is likely in the wiring. If it's normal, replace the ECT sensor.
- 44. If replacing the ECT sensor, clear the fault code and recheck after installation. If code reappears, further inspect wiring and ECM.
Common causes
- Faulty ECT sensor
- Shorted signal wire
- Open circuit or poor ground connection
- Corroded connector pins
- Incorrect sensor installation
Typical repair cost
$$$
Related codes
Frequently asked questions
Can I drive the vehicle with this code?
It's drivable but you may experience poor performance and incorrect engine temperature readings. Fix soon.
Will this code come back after I clear it?
If the underlying issue isn't fixed, yes, the code will likely return.
Why is this paired with SPN 6322?
SPN 6322 indicates a low voltage condition on the same sensor circuit, showing potential intermittent issues.
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