Engine Coolant Temperature Sensor Circuit Range/Performance Problem
There's a problem with the engine coolant temperature sensor reading.
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's computer is getting weird signals from the coolant temperature sensor, suggesting it's not reading the actual coolant temperature correctly.
What the computer is actually seeing
The Engine Control Module (ECM) compares the input from the engine coolant temperature sensor against expected values; a significant discrepancy triggers this code.
What a healthy reading looks like
Typically, the engine coolant temperature should be between 190°F and 220°F (88°C to 104°C) when running; sensor readings should be within 0.5V to 4.5V depending on temperature.
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. Inspect the wiring and connectors at the coolant temperature sensor for any visible damage or corrosion. Correct if necessary. Decision: Are they good? If yes, go to step 2. If no, repair or replace the damaged components before retesting.
- 22. Measure the resistance of the coolant temperature sensor at various coolant temperatures. It should decrease with increasing temperature. Decision: Do readings match expected resistance values? If yes, go to step 3. If no, replace the coolant temperature sensor.
- 33. Use a scan tool to monitor live data. Check the coolant temperature reading against the actual engine temperature. Decision: Does the reading match what you expect? If yes, consider other potential issues. If no, replace the coolant temperature sensor.
Common causes
- Faulty engine coolant temperature sensor
- Wiring issues or connector problems
- Coolant leaks affecting sensor function
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's drivable, but monitor for overheating and fix soon to avoid engine damage.
Will this code come back after clearing?
If the underlying issue isn't fixed, it likely will return.
Why am I seeing other codes with this?
Often, temperature sensor issues can trigger related codes for performance and efficiency.
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