ECM pmCAN Module Instruction Manual page 10

3. When the engine (and hence exhaust flow) stops, the dendrites on the electrodes will point
directly at each other.
electrodes and the high voltage across the electrodes will cause a slow "tree-trimming"
effect.
A sensor will be deseeded if it is blown out with compressed air, if it is left "on" in stationary
exhaust or air, or if it is struck by liquid water. How long it takes for the sensor to be
reseeded is a function of the density of PM in the exhaust and the exhaust flowrate. The
higher the density of PM and the greater the exhaust flowrate, the less the time for reseeding.
4
This will substantially reduce the effective gap between the
Figure 1: PM Sensor