Fault Code for Engine Coolant Temperature Sensor Range/Performance Problem
Indicates an issue with the engine coolant temperature sensor.
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 coolant temperature sensor is not providing readings that match expected temperatures, meaning it might be faulty or the wires are bad.
What the computer is actually seeing
The engine control module (ECM) expects the engine coolant temperature to be between 190°F and 220°F (88°C to 104°C) during normal operation but is receiving a voltage signal that's either too low (close to 0.3V) or too high (over 4.5V).
What a healthy reading looks like
Engine coolant temperature should ideally read between 190°F and 220°F (88°C to 104°C) under normal operating conditions.
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 for the coolant temperature sensor for damage or corrosion. Decision: If found, repair wiring; if not, proceed to step 2.
- 22. Check the coolant level in the reservoir. Decision: If low, refill to the proper level and monitor; if not, proceed to step 3.
- 33. Use a scan tool to monitor the coolant temperature reading at engine idle. Decision: If reading is abnormal (below 190°F or above 220°F), replace the coolant temperature sensor; if normal, proceed to step 4.
- 44. Check voltage at the sensor connector with the engine on. It should be around 2.5V to 4.5V. Decision: If voltage is out of range, check the ECM and wiring; if in range, the problem may be in the ECM.
Common causes
- Faulty engine coolant temperature sensor
- Wiring issues or corrosion in the connector
- Coolant leaks affecting temperature readings
- ECM software error or corruption
Typical repair cost
$$-$$$
Related codes
Frequently asked questions
Is it safe to drive with this code present?
It's generally safe to drive, but engine performance may be affected, so fix it soon.
Will this code come back after clearing?
If the underlying issue is not fixed, this code will likely return.
Why does this code sometimes pair with engine overheating issues?
If the sensor is faulty, it can give incorrect readings, leading to improper fueling or cooling, potentially causing overheating.
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