Specifications

10–14 Troubleshooting
Publication 1747-6.2
The Following
Error Exists
Probable Cause Recommended Action
System
Inoperable,
No ao PU
User Program
Logic Error
1. Monitor logic in Run mode and verify desired I/O
status.
2. Check for minor CPU faults.
Refer to your programming software user manual.
No
M
a
j
o
r C
PU
Faults Detected
Defective I/O
Devices or I/O
Wiring
Test inputs and outputs according to I/O troubleshooting
procedures starting on page 10–26.
The Following
Error Exists
Probable Cause Recommended Action
CPU Memory
Error
Cycle power.
CPU Fault
Faulty Memory
Module
1. Remove power and then remove the memory module
from the processor.
2. Re-install the processor and re-apply power to the
power supply.
If steady FLT LED changes to flashing, replace the existing
memory module with a replacement module.
Refer to chapter 6 for removing and installing memory
modules.
C
PU
F
ault
Faulty CPU/Power
Supply
1. Place the processor in another chassis not in the
existing system and cycle power. If steady FLT LED
reappears, replace the processor.
2. If FLT LED clears, monitor the line power going to the
power supply in existing system.
3. Replace existing system power supply if line power
checks OK.
Processor
Firmware Installed
Incorrectly
If upgrading the processor to a different firmware level,
verify firmware chip orientation matches the upgrade kit
directions.
Refer to the following key to determine the status of
the LED indicators:
Indicates the LED is OFF.
Indicates the LED is ON.
➀
The DH485 LED on the SLC 5/03 processor is labeled DH+ on
the SLC 5/04 processor, and ENET on the SLC 5/05 processor.
Indicates the LED is FLASHING.
Status of LED does not matter.
POWER
RUN
FLT
BATT
FORCE
DH485
RS232
If the LEDs indicate:
➀
POWER
RUN
FLT
BATT
FORCE
DH485
RS232
If the LEDs indicate:
➀