prjctx.net
P047APowertrainMonitor

Exhaust Pressure Sensor "B" Circuit

This code means the PCM/ECM has detected a fault affecting exhaust pressure sensor "b" circuit. This can keep the emissions system from working correctly, which may raise tailpipe emissions, reduce fuel economy, and prevent readiness monitors from completing.

Monitor closely — watch for other symptoms. Safe to drive short distances for now.

What You Might Notice

  • Check Engine Light illuminated
  • Reduced fuel economy
  • Failed emissions or readiness monitor
  • Rough idle or hesitation
  • Possible exhaust smell or smoke

Most Common Causes

  1. 1

    Failed sensor, valve, heater, or emissions actuator

  2. 2

    Wiring damage or poor electrical connection

  3. 3

    Carbon buildup, restriction, or exhaust leak

  4. 4

    Vacuum leak or pressure hose issue

  5. 5

    PCM/ECM fault or outdated calibration

How to Diagnose It

  1. 1

    Check Failed sensor, valve, heater, or emissions actuatorInspect for signs of failure and test before replacing.

  2. 2

    Check Wiring damage or poor electrical connectionInspect for signs of failure and test before replacing.

  3. 3

    Check Carbon buildup, restriction, or exhaust leakInspect for signs of failure and test before replacing.

  4. 4

    Check Vacuum leak or pressure hose issueInspect for signs of failure and test before replacing.

  5. 5

    Check PCM/ECM fault or outdated calibrationInspect for signs of failure and test before replacing.

How to Fix It

  1. 1

    Inspect the sensor, valve, heater, and related hoses or pipes

  2. 2

    Repair wiring or connector damage

  3. 3

    Clean carbon buildup or repair leaks/restrictions

  4. 4

    Replace the failed emissions component if testing confirms it

  5. 5

    Clear the code and run the monitor to verify the fix

Need a deeper diagnosis?

Search for related repair guides or browse by system.