P2BA8 concerns NOx exceedance with interrupted reagent dosing.
Meaning, symptoms, causes and checks
P2BA8 concerns NOx exceedance with interrupted reagent dosing. The fault label reports a NOx exceedance associated with interruption of reagent dosing. The definition links the emissions result with interrupted dosing. It does not establish which pump, sensor, control unit or other part caused the interruption.
Affected system: Reductant dosing and SCR aftertreatment
Symptoms
- Warning light may illuminate
- Related system function may be impaired
- Vehicle-specific symptoms vary
Possible causes
- Implausible sensor or switch signal, poor ground, connector corrosion, or wiring damage
- Related wiring, connector, power or ground fault
- Vehicle-specific mechanical or control issue
What to check
- Record stored and pending codes and freeze-frame data
- Compare the named sensor or switch signal with actual operating conditions; inspect the connector, reference supply, ground and harness.
- Confirm measured values against the vehicle service information
- Retest under the conditions that set the code
- Compare the named sensor or switch signal with actual operating conditions; inspect the connector, reference supply, ground and harness.
- Repair the verified cause and confirm the code does not return
Also written as: P2BA8-00, P2BA800 (some scan tools add the fault-type byte, e.g. -00).