P2045 moderate

Reductant Temperature Sensor Circuit High

The P2045 code means the vehicle's onboard diagnostic system has detected: Reductant Temperature Sensor Circuit High. 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 warning light on
  • SCR system may overdose DEF
  • Reduced engine power possible
  • Speed limiter warning on dashboard

Probable Causes (Ranked by Likelihood)

  • Short to voltage in DEF temperature sensor wiring Very High
  • Defective DEF temperature sensor High
  • Open ground in sensor circuit Moderate
  • Corroded DEF tank connector Moderate
  • PCM input driver issue Low

Step-by-Step Diagnostic Procedure

  1. Read freeze frame data for P2045

  2. Check DEF temperature sensor wiring for shorts to voltage

  3. Verify sensor ground integrity at the connector

  4. Compare sensor reading to independent temperature measurement

Frequently Asked Questions

What does P2045 mean?

P2045 means the DEF temperature sensor circuit is reading above the maximum expected voltage, typically from a wiring short to voltage or an open ground wire.

Can I drive with a P2045 code?

Short-distance driving is possible, but the SCR system will not function correctly and some vehicles may impose driving restrictions.

How much does it cost to fix P2045?

Expect $150 to $500 for sensor replacement or wiring repair, depending on vehicle configuration.

Sources

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

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