The P2043: Reductant Temperature Sensor Circuit Range/Performance code indicates that the reductant (DEF/AdBlue) temperature sensor is not performing within the expected range. This could be due to a faulty sensor, incorrect performance, or issues with the sensor’s wiring or connectors.
P2043 – Quick Overview
Code | Information |
---|---|
Meaning | P2043: Reductant Temperature Sensor Circuit Range/Performance |
Is it serious? | Yes, if the temperature sensor is not performing correctly, it may lead to improper DEF injection, reducing NOx reduction efficiency and increasing emissions. |
Possible causes | – Faulty reductant temperature sensor – Incorrect sensor performance – Wiring or connector issues |
How to diagnose? | – Test the sensor for range and performance – Inspect wiring and connectors – Verify sensor operation |
P2043 Meaning
The P2043: Reductant Temperature Sensor Circuit Range/Performance code signifies that the reductant temperature sensor is not providing readings within the expected range. The temperature sensor monitors the temperature of the DEF fluid to ensure it is within the optimal range for proper injection into the exhaust system. If the sensor is faulty or malfunctioning, the DEF system may not function properly, leading to poor emissions control.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for additional codes related to the DEF system or emissions. Other codes may provide further insight into the issue. | OBD-II Scanner |
Test the Reductant Temperature Sensor | Use a multimeter or diagnostic tool to test the sensor’s range and performance. Compare the sensor’s readings to manufacturer specifications to determine if it is functioning properly. | Multimeter, Diagnostic Tool |
Inspect Wiring and Connectors | Visually inspect all wiring and connectors connected to the reductant temperature sensor. Look for signs of damage, corrosion, or loose connections that could affect sensor performance. | Flashlight, Multimeter |
Check Sensor Circuit Continuity | Perform a continuity test on the sensor circuit wiring to ensure there are no shorts, breaks, or high resistance causing poor performance in the circuit. | Multimeter |
Inspect the Reductant System | Inspect the overall reductant (DEF) system, including the tank and fluid lines, to ensure no blockages or contamination are affecting the temperature sensor’s readings. | Flashlight, Diagnostic Tool |
Replace the Reductant Temperature Sensor | If the temperature sensor is determined to be faulty or providing inaccurate readings, replace it with a new one. Ensure it is properly installed to prevent further issues. | Replacement Sensor, Wrench |
Repair or Replace Damaged Wiring | Repair or replace any damaged wiring, connectors, or circuit components to restore proper sensor operation and ensure accurate readings. | Wiring Repair Kit |
Clear the Code and Test Drive | After repairs, clear the P2043 code using an OBD-II scanner. Take the vehicle for a test drive to ensure that the sensor operates within the correct range and that the issue is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to verify that the P2043 code has not returned. | OBD-II Scanner |

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