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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What Are the Symptoms of P2043?
- Check Engine Light illuminated
- DEF system malfunction warning
- Inaccurate DEF temperature readings
- SCR efficiency issues
- Possible engine power reduction
What Causes P2043? (Most Likely First)
- 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
Can I Still Drive with P2043?
Short distances only. P2043 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
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
How Do You Diagnose P2043?
-
Read freeze frame data and confirm P2043
-
Compare DEF temperature sensor reading to ambient temperature at cold start
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Inspect DEF fluid quality and check for contamination
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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)
Which Vehicles Commonly Get P2043?
- 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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