Service guide
March 2001
7
Where possible, verify the hypothesis regarding the cause of an
experienced problem by trying to replace the suspect part or system.
Make only one replacement between these tests and go back to the
originally fitted part or system, when there is no effect of the
replacement.
All sensors are using an optical principle, where the effect is that of a
light path being intersected by a moving part or by the medium. All
sensors are equipped with monitoring LED’s with the following functions:
PS01:
Green LED on means that the signal is stable and
unambiguous.
Red/orange LED on means light path is cut by an object
(“dark”).
PS02-05:
A red LED means, that the light path is
not
cut by an
object (opposite of “dark”).
These functions serve to help identifying certain sensor related faults
before trying to replace the sensor itself.
