P04A8 OBD II Trouble Code Exhaust Pressure Control Valve B Position Sensor/Switch Circuit Low

How to quickly diagnose, repair, and info on symptoms and causes of a P04A8 code that indicates a low voltage in the B exhaust pressure control valve position sensor circuit.

Symptoms of P04A8 OBD II Trouble Code

  • Illuminated check engine light
  • Increased emissions
  • Poor engine performance
  • Hard starting

Common Causes of P04A8 OBD II Trouble Code

  • Faulty exhaust pressure control valve
  • Wiring problems
  • Faulty PCM

Severity of P04A8 OBD II Trouble Code

The severity of this code is moderate to severe. It's a good idea to address this code as soon as possible.