P2C21 — Engine Oil Temperature Sensor A/B Correlation
The signals of engine oil temperature sensors A and B do not correlate within the calibrated tolerance. One sensor drifts or installation offset between the two channels.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Engine oil temp sensor a
- Engine oil temp sensor b
- Ecm
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- One sensor characteristic drifted
- Harness incorrectly swapped between channels
Diagnostic notes
- The malfunction indicator lamp may illuminate
Sources
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
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.