P2046 moderate

Reductant Temperature Sensor Circuit Intermittent

The P2046 code means the vehicle's onboard diagnostic system has detected: Reductant Temperature Sensor Circuit Intermittent. 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 on intermittently
  • DEF warning may appear and disappear
  • SCR system intermittent faults
  • Occasional engine power reduction
  • CEL may reset and return

Probable Causes (Ranked by Likelihood)

  • Loose connector at DEF temperature sensor Very High
  • Intermittent wiring break from vibration High
  • Failing DEF temperature sensor Moderate
  • Corroded pin connections Moderate
  • PCM intermittent input fault Low

Frequently Asked Questions

What does P2046 mean?

P2046 indicates an intermittent fault in the DEF temperature sensor circuit, usually from a loose or corroded connection that causes the signal to fluctuate.

Can I drive with a P2046 code?

Short-distance driving is fine, but the intermittent fault may cause unpredictable SCR system behavior.

How much does it cost to fix P2046?

Repairs typically cost $150 to $500, often involving connector repair or wiring harness work.

Mechanics Guide Step-by-step diagnosis

Step-by-Step Diagnostic Procedure

  1. Confirm P2046 and review freeze frame conditions

  2. Wiggle-test DEF sensor connector while monitoring signal

  3. Inspect connector pins for corrosion and proper tension

  4. Check wiring routing for chafing or exposure to road spray

Sources 2

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

Commonly Affected Vehicles

  • 2011-2019 Chevrolet Silverado 2500 6.6L Duramax
  • 2009-2015 Volkswagen Jetta 2.0L TDI
  • 2012-2018 BMW 328d 2.0L Diesel
  • 2010-2016 Mercedes-Benz ML350 3.0L BlueTEC

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