Powertrain Definition only Lights the check engine lamp

P2046: Reductant Temperature Sensor A Circuit Intermittent

Standardized SAE J2012 code · P20xx — Fuel & air metering and auxiliary emission controls

What does P2046 mean?

Reductant temperature sensor A signal jumps or drops out intermittently — connector or harness fault.

The code tells you which monitor failed, not which part is broken. Test before replacing parts.

Symptoms

  • Check engine light or NOx warning on
  • AdBlue/DEF level or quality warning
  • Possible no-start countdown after ignore period
  • Failed emissions inspection (NOx)

Common causes

  • High Intermittent connector
  • Low Connector with intermittent contact under vibration
  • Low Harness routed against vibrating component

Likelihood is a general estimate across vehicles; your make and model may differ.

Add your car to see reports of P2046 on the same make and model first.

P2046 in the community

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