Device for diagnosing dosing system, which meters reagent in exhaust gas passage of internal combustion engine, has pump and reagent for applying working pressure, where dosing valve is provided for metering

摘要

The device has a pump (14), a reagent (12) for applying a working pressure (pB). A dosing valve (16) is provided for metering. An external module is provided for insertion in a reagent path (15) between the pump and the dosing valve. The external module has an electrically controllable shut-off valve (27) and a diagnosis pressure sensor (28). Independent claims are included for the following: (1) a method for operating a diagnosis device; and (2) a computer program for computer program product for executing the method.