Operating Instructions
LMS1xx Laser Measurement Sensors 
Troubleshooting
8012471/ZN27/2017-06-09 © SICK AG · Germany · All rights reserved · Subject to change without notice 89
Chapter 9
9 Troubleshooting
Claims under the warranty rendered void!
The housing screws of the LMS1xx are sealed. Claims under the warranty against SICK AG 
will be rendered void if the seals are damaged or the device opened. The housing is only 
allowed to be opened by authorized service personnel.
This chapter describes how to identify and rectify errors and malfunctions of the LMS1xx.
9.1 In the event of faults or errors
Cease operation if the cause of the malfunction has not been clearly identified!
Stop the machine/system if you cannot clearly identify or allocate the error and if you 
cannot safely rectify the malfunction.
9.2 Error displays of the LEDs
Important On the LMS12x the status indicators are switched off so that as far as possible it cannot be 
seen that the device is part of an object protection system. In the practice check mode they 
are switched on.
Display Possible cause Rectification of the error
ÙandØoff 
No operating voltage, or 
voltage too low
 Check the voltage supply and activate, 
if
 necessary.
Ðilluminated
Optics cover contamina-
ted, still in operation
 Clean the optics cover.
Ð flashes with 1 Hz
Optics cover contamina-
ted, no operation
 Clean the optics cover.
Ð flashes with 4 Hz
System error  Pay attention to the error display of the 
7segment display or carry out a 
diagnostics with the aid of SOPAS ET.
 Switch the device off and back on again.
Tab. 36: Error displays of the LEDs