P2182 Code – What Does It Mean & How To Fix It

This is one of the most frequent OBD2 trouble codes. Read the full article below to know what it means, how to fix it, and what other codes may show related to it.

With varying coolant temperatures, the PCM ground signal's resistance changes. Engine resistance is highest when the engine is cold. The resistance of the engine is lowest when it is warm. PCMs will set P2182 if they detect an abnormal voltage condition.

Causes

• The engine control module (ECM) compares the ECT sensors with one another and the ambient air temperature sensor when the engine is first powered up.
• When compared to the other sensors, the ECT sensor does not read correctly.

Symptoms

• This code must be set in ECM memory as a fault in order to illuminate the Check Engine light.
• If the same problem occurs each time the engine is cold-started, the ECM will ignore the ECT #2 sensor.

Diagnosis

• Codes are scanned and recorded in the ECM and freeze frame data is examined for failures.
• A scan is only performed once the engine has been at ambient temperature and has sat for at least 8 hours.
• During this process the ECM is scanned and the ECT #2 sensor and the ambient air temperature sensor are checked for differences. Ideally, all three should be in close proximity.
• Ensure the ECT sensor connectors are free of problems such as corroded or loose pins.

Common mistakes

• Clearing ECM memory codes before checking freeze frame data for possible main failures, so the failure can be duplicated
• When the ECM codes are fixed, but the system is not allowed to return to normal because the ECM has not been cleare
• Replace the ECT sensor before repairing the connector

How serious is this?

If the second sensor fails, the engine may have issues running and the P2182 code indicates that the ECT sensors are not matching. In a test for emissions, this will result in a failure.

What repairs can fix the code?

• Sensor #2 of ECT needs to be replaced.
• Make sure the ECT sensor is connected properly.
• ECT #2 sensor wiring needs to be repaired.

Related codes

None listed.

Conclusion

If the second sensor fails, the engine may have issues running and the P2182 code indicates that the ECT sensors are not matching. In a test for emissions, this will result in a failure. With varying coolant temperatures, the PCM ground signal's resistance changes. Engine resistance is highest when the engine is cold. The resistance of the engine is lowest when it is warm. PCMs will set P2182 if they detect an abnormal voltage condition.