
7.1 Troubleshooting table
Table 4: Troubleshooting
LED indicator/fault pattern Cause Measures
Green LED does not light up No voltage or voltage below
the limit values
Check the power supply,
check all electrical connec‐
tions (cables and plug connec‐
tions)
Green LED does not light up Voltage interruptions Ensure there is a stable power
supply without interruptions
Green LED does not light up Sensor is faulty If the power supply is OK,
replace the sensor
Yellow LED flashes Sensor is still ready for opera‐
tion, but the operating condi‐
tions are not ideal
Check the operating condi‐
tions: Fully align the beam of
light (light spot) with the
reflector / Clean the optical
surfaces (sensor and reflec‐
tor) / Readjust the sensitivity
(potentiometer) / If the poten‐
tiometer is set to the max.
sensitivity: Reduce the dis‐
tance between the sensor and
the reflector, and check the
reflector type / Reflector is not
suitable for the application in
question (we recommend only
using SICK reflectors)/ Check
sensing range and adjust if
necessary, see table 3. / Dis‐
tance between the sensor and
the reflector is too long
Signal interruptions when
object is detected
Depolarizing property of the
object surface (e.g., tape),
reflection
Reduce sensitivity or change
the position of the sensor
8 Disassembly and disposal
The sensor must be disposed of according to the applicable country-specific regula‐
tions. Efforts should be made during the disposal process to recycle the constituent
materials (particularly precious metals).
9 Maintenance
SICK sensors are maintenance-free.
We recommend doing the following regularly:
•Clean the external lens surfaces
•Check the screw connections and plug-in connections
No modifications may be made to devices.
Subject to change without notice. Specified product properties and technical data are
not written guarantees.
7 TROUBLESHOOTING
10 8021851 | SICK
Subject to change without notice