I/O Faults - Siemens SIMATIC S5-100U System Manual

Diagnostics and Troubleshooting

5.4 I/O Faults

Fault
Module with fault
no
indication
(red LED)
yes
no
Red LED lights.
yes
no
Module power
supply ok?
yes
yes
Short circuit at
the outputs?
no
no
Defective fuse
yes
Replace fuse.
Figure 5-5. Analyzing the Cause of a Fault in the I/Os
5.5 System Parameters
The "SYSPAR" programmer function makes it possible to read out the system parameters (e.g.,
CPU software version) of the programmable controller (see programmer manual).
5-12
Power supply ok?
yes
Module addressable via
the process input image
(PII) and the process out-
put image (PIQ) (STA-
TUS VAR, FORCE VAR)
Check no
supply
leads.
Bus connection ok?
Eliminate yes
short
Replace module with
circuit.
simulator module.
Is a check with STATUS
VAR or FORCE VAR
possible?
Defective
module
no
Check connections of
other bus units and
interface modules.
S5-100U
Check supply
no
leads.
- Check module
yes
(exchange).
- Check program.
no
Replace bus unit.
yes
Replaced module
is defective.
EWA 4NEB 812 6120-02b