Fail-Safe Modules   
7.6 EM 4 F-DI/3 F-DO DC24V PROFIsafe digital electronic module 
  ET 200S Distributed I/O System - Fail-Safe Modules 
158  Installation and Operating Manual, 08/2008, A5E00103686-07 
Causes of Faults and Corrective Measures    
The following table contains the possible causes of the faults described for the individual 
diagnostic messages of the EM 4 F-DI/3 F-DO DC24V PROFIsafe and remedies. 
Table 7- 33  Diagnostic messages of the EM 4 F-DI/3 F-DO DC24V PROFIsafe, causes of errors and 
remedies 
Diagnostic 
Message 
Fault 
detection 
Possible Causes  Corrective Measures 
Short circuit in the sensor/actuator  Eliminate the short-circuit. 
Cross-circuit at the sensor/actuator Eliminate the cross-circuit within 
100 hours after the error has 
occurred. 
Encoder supply short circuit  Eliminate the short-circuit. 
Short-circuit  Depends 
on 
parameter 
settings 
Internal error  Replace module 
Internal error  Always  Internal module fault has occurred  Replace module 
Inserted module does not match 
configuration 
Faulty parameter assignment 
Correct configuration (compare 
actual and preset configuration)  
Check communication paths 
Correct configuration 
Parameter 
assignment 
error 
Always 
PROFIsafe address set incorrectly 
in the F-module 
Check whether the PROFIsafe 
address on the module matches 
the configuration in 
HW Config
 
Sensor 
voltage or 
load voltage 
missing 
Always  No supply voltage or supply 
voltage is too low 
Check the supply voltage on the 
interconnected PM, 
Check module for correct contact 
Error in communication between F-
CPU and module due to defective 
PROFIBUS connection or higher 
than permissible EMI, for example 
Check the PROFIBUS/PROFINET 
connection 
Eliminate the interference 
PROFIsafe monitoring time set too 
low 
Set a greater value for the "F 
monitoring time" parameter for the 
module in 
HW Config
 
Communicati
on error 
Always 
Configuration of the F-module 
does not match safety program 
Generate safety program again; 
then load configuration and safety 
program into F-CPU again 
Faulty process signal 
Defective sensor 
Check process signal, replace 
sensor if necessary 
Short circuit between unconnected 
sensor cable and the sensor 
supply cable 
Eliminate short circuit 
Wire break in connected sensor 
cable or the sensor supply cable 
Eliminate broken wire 
Assigned discrepancy time too 
short 
Check the assigned discrepancy 
time 
Safety-
related 
shutdown 
Always 
Switching frequency exceeded  Reduce the switching frequency 
  Once the fault is eliminated, the F-
module must be reintegrated in the 
safety program 
Detailed information on F I/O access can be found under 
"Diagnostics"
 in the 
S7 Distributed 
Safety, Configuring and Programming
 manual or the 
S7 F/FH Systems, Configuring and 
Programming
 manual.