P20BA — Reductant Heater A Control Circuit Performance

P20BA: Reductant Heater A Control Circuit Performance — what it means, the affected system and what to check before replacing parts.

Meaning, symptoms, causes and checks

Reductant Heater A Control Circuit Performance. Basic catalogue definition; diagnostic details have not yet been reviewed.

Affected system: Powertrain

Symptoms

  • An engine or SCR warning may be displayed.
  • Reduced engine output is possible if the vehicle activates emissions-related restrictions.

Possible causes

  • Reductant heater A may fail to achieve the commanded operating response.
  • Damaged wiring, poor contacts, a temperature-sensor fault or heater failure may contribute.

What to check

  • Read related SCR faults and inspect reductant-heater and temperature-sensor connectors.
  • Observe heater operation and temperature data with a compatible diagnostic tool if supported.
  • Check heater supply and resistance to vehicle specifications before suspecting control electronics.

Also written as: P20BA-00, P20BA00 (some scan tools add the fault-type byte, e.g. -00).