Patent ID: 8773143
Filing Date: 2014-07-08
Classification: F02B,F02D,G01N,G01R

Abstract:
1. A method for identifying cable faults at the terminals of a broadband lambda probe ( 60 ) comprising a Nernst cell ( 61 ) and a pump cell ( 62 ) in an exhaust gas duct of an internal combustion engine, wherein the broadband lambda probe ( 60 ) has a reference electrode terminal RE, an internal pump electrode terminal IPE and an external pump electrode terminal APE, wherein, via a control unit ( 10 ), a pump current is applied to the broadband lambda probe ( 60 ) by a pump current source SQ ( 20 ) and a pulsed reference pump current is applied to the broadband lambda probe ( 60 ) by a reference current source SQr ( 21 ), wherein the pump current source SQ ( 20 ) and the reference current source SQr ( 21 ) are mutually connected to the terminals of the broadband lambda probe ( 60 ), a grounding resistor R GND ( 64 ) and a reference voltage source U Ref ( 23 ) with the aid of a first switching matrix ( 11 ) and wherein the first switching matrix ( 11 ) enables at least the switching connections: Z_ Z_ Z_ Z_Rie: RE with SQr and IPE with VM, characterized in that in order to identify the cable faults at least at times a controlled pump current is conducted through the pump cell (