Engine Coolant Temperature Sensor 1/2 Correlation
ECT sensors 1 and 2 readings disagree beyond plausible limits — typically near startup both should match within tolerance.
Affected components
- Ect sensor 1
- Ect sensor 2
Common causes
- High likelihood: One sensor drifted
Possible symptoms
- Check engine light on
- Cooling fan runs constantly or not at all
- Cabin heater weak or excessively hot
- Possible long warm-up time or hard cold start
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.