Troubleshooting Your 5/03
Between the time you apply power to the 5/03 processor and it has a chance
to establish communication with a connected programming device, the only
form of communication, between you and the 5/03 processor is through the
When power is applied, all of the LEDs flash on and then off while the
processor conducts hardware tests. This is part of the normal powerup
sequence. Following the self test by the processor, all the LEDs against flash
on momentarily. If a user program is in a running state, the RUN LED will
be on. If a fault exists within the processor, the FLT LED is on.
To receive the maximum benefit of this troubleshooting section, we
recommend you follow these steps:
Identify the status of your processor LEDs. See chapter 4 for description
of LEDs and their different states.
Using the tables on the following pages, match your processor and power
supply LEDs with the status LEDs located in the first column.
Once the status LEDs are matched to the appropriate table, simply move
across the table identifying error description aid probable causes.
Then follow the recommended action steps for each probable cause until
the cause is identified
If recommended actions do not identify the trouble cause, contact your
local Allen-Bradley sales office or distributor.
Clearing 5/03 Processor Faults Using the Keyswitch
Toggle the keyswitch from RUN to PROG and then back to RUN, this clears
the fault. If the keyswitch is left in the RUN position, the processor mode
cannot be changed from a programmer/operator interface device. If you
return the keyswitch to the REM position, you can then use a
programmer/operator interface device to change the processor mode.
ATTENTION: If you clear a processor fault using the
keyswitch, the processor immediately enters the Run mode.