Electrostatic Particle Sensors

A computer program product comprising a computer-readable medium and program code stored on the computer-readable medium and which, when it is executed on a processor, directs the processor to:

• generate a sensor current with the particle sensor having a first electrode and a second electrode, wherein the first electrode and the second electrode define a gap through which the exhaust gas flows between the electrodes, by applying a difference in potential between the electrodes, wherein soot particles accumulate on the electrodes and, after a dwell time dependent on the preloading of the electrodes with soot particles, they move from a first electrode to the respective second electrode generating a flow of current as a measure of the quantity of soot in the stream of exhaust gas;
• determine whether a peak in the sensor current is measured after the switching off of the internal combustion engine;
• and
• if no peak in the sensor current is measured, flag the particle sensor as faulty.