Peugeot P15B3 error code diagnostics and repairs

The P15B3 error code in Peugeot diesel vehicles indicates a fault related to additive dosing, which can affect either the AdBlue (SCR) system or the FAP (particulate filter) additive system depending on the specific engine and year.

In SCR-equipped models, the error relates to the AdBlue circuit, involving components such as the pump, pressure sensor, temperature sensor, injector, or wiring harness. This can trigger warnings such as ‘AdBlue’ or ‘Impossible to start in XXX km’.

In models using FAP additives (such as Eolys), the code points to the additive circuit, including the reservoir, pump, or additive counter. Failure to address these issues can lead to ineffective regeneration, clogged filters, and reduced engine performance.