Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is getting different readings from two sensors that measure how hot the engine oil is. It's like if you had two thermometers in a pot of soup, and they showed different temperatures.
The engine control module (ECM) is detecting a discrepancy between the readings of two engine oil temperature sensors. These sensors are supposed to provide similar readings, and a significant difference triggers this code.
The P2C21 code is set when the ECM detects a correlation issue between the engine oil temperature sensors A and B. These sensors are used to monitor the oil temperature to ensure optimal engine performance and protection. A mismatch in their readings indicates a potential fault in one of the sensors or their circuits.
• Check Engine Light illuminated
• Inaccurate engine oil temperature readings
• Possible engine performance issues
• Faulty engine oil temperature sensor A or B
• Wiring issues or poor connections in the sensor circuit
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for both sensors.
• Test the sensors individually for proper operation.
• Replace the faulty engine oil temperature sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $300
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and maintain sensor wiring and connections.
• Perform routine engine oil checks and changes.
• Ensure ECM updates are applied as recommended.
Sensor Issue
• Do not ignore the Check Engine Light.
• Seek professional diagnosis to prevent engine damage.
Check your vehicle's warranty for coverage on sensors and ECM components.
This code has been associated with sensor discrepancies in various vehicle models, often due to wiring issues.
Moderate – Addressing this issue promptly can prevent potential engine damage.
Driving with a faulty engine oil temperature sensor can lead to engine damage. Ensure repairs are conducted by a qualified technician.
• Engine at normal operating temperature
• Vehicle stationary
The engine oil temperature sensors are typically located near the oil filter or oil pan.
Q: Can I drive with a P2C21 code?
A: It's not recommended to drive for extended periods with this code, as it could lead to engine damage.
Q: How do I know which sensor is faulty?
A: A diagnostic scan and testing by a professional can determine which sensor is faulty.
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