AI Diesel Tech
P2456OBD-IIAFTERTREATMENT

Diesel Particulate Filter Pressure Sensor A Circuit Intermittent

Common Symptoms

  • Check engine light illuminated
  • Reduced engine power or derate
  • Poor acceleration under load
  • Intermittent engine performance issues
  • Regeneration cycle may not complete properly

Most Likely Root Causes

  • Damaged or corroded wiring harness to DPF pressure sensor
  • Faulty DPF differential pressure sensor
  • Poor electrical connection at sensor connector
  • Intermittent short or open circuit in sensor wiring
  • Water or debris contamination in sensor connector

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Component Location

DPF differential pressure sensor is typically mounted on or near the diesel particulate filter assembly in the exhaust system.

Manufacturer Notes

This intermittent code often indicates a marginal electrical connection that fails under heat, vibration, or moisture exposure conditions.

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