Reductant Temperature Sensor Circuit Range/Performance
The P2043 code means the vehicle's onboard diagnostic system has detected: Reductant Temperature Sensor Circuit Range/Performance. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- moderate
- Estimated cost
- $150 - $500 (parts and labor)
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Common Symptoms
- Check Engine Light illuminated
- DEF system malfunction warning
- Inaccurate DEF temperature readings
- SCR efficiency issues
- Possible engine power reduction
Probable Causes (Ranked by Likelihood)
- Degraded DEF temperature sensor Very High
- Crystallized or contaminated DEF affecting sensor High
- Intermittent sensor connection Moderate
- DEF tank heater malfunction affecting readings Moderate
- PCM calibration issue Low
Frequently Asked Questions
What does P2043 mean?
P2043 means the DEF temperature sensor is reporting values outside the expected operating range, which could be caused by a degraded sensor or contaminated DEF fluid.
Can I drive with a P2043 code?
Short-distance driving is safe, but the SCR system may not dose DEF correctly, affecting emissions performance.
How much does it cost to fix P2043?
Expect $150 to $500, which may include DEF tank sender replacement or fluid flush if contaminated.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
-
Read freeze frame data and confirm P2043
-
Compare DEF temperature sensor reading to ambient temperature at cold start
-
Inspect DEF fluid quality and check for contamination
-
Monitor sensor reading during warm-up for logical temperature progression
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
Commonly Affected Vehicles
- 2014-2020 Ram 3500 6.7L Cummins
- 2011-2017 Ford F-350 6.7L Power Stroke
- 2012-2019 Chevrolet Silverado 3500 6.6L Duramax
- 2010-2015 Audi A3 2.0L TDI
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