P2043 moderate

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.

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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

Step-by-Step Diagnostic Procedure

  1. Read freeze frame data and confirm P2043

  2. Compare DEF temperature sensor reading to ambient temperature at cold start

  3. Inspect DEF fluid quality and check for contamination

  4. Monitor sensor reading during warm-up for logical temperature progression

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.

Sources

This page is built from documented references. Verify against your own service info before repair work.

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