Allen-Bradley MicroLogix 1200 Reference Manual page 386

D-4 Fault Messages and Error Codes
Error Advisory Message
Code
(Hex)
0016 STARTUP
PROTECTION FAULT
0017 NVRAM/MEMORY
MODULE USER
PROGRAM
MISMATCH
0018 MEMORY MODULE
USER PROGRAM
INCOMPATIBLE WITH
OS
001A USER PROGRAM
INCOMPATIBLE WITH
OS AT POWER-UP
0020 MINOR ERROR AT
END-OF-SCAN
DETECTED
0021 EXPANSION POWER
FAIL (EPF)
(MicroLogix 1500 only)
IMPORTANT
0022 WATCHDOG TIMER
EXPIRED, SEE S:3
0023 STI ERROR
Publication 1762-RM001C-EN-P
Description
The user fault routine was executed
at power-up, prior to the main ladder
program. Bit S:1/13 (Major Error
Halted) was not cleared at the end of
the User Fault Routine. The User
Fault Routine ran because bit S:1/9
was set at power-up.
Bit S:2/9 is set in the controller and
the memory module user program
does not match the controller user
program.
The user program in the memory
module is incompatible with the OS.
The user program is incompatible
with the OS.
A minor fault bit (bits 0-7) in S:5 was
set at the end of scan.
A power failure is present on the
expansion I/O bank.
This error code is present only when
the controller is powered, and power
is not applied to the expansion I/O
bank. This is a self-clearing error
code. When power is re-applied to
the expansion I/O bank, the fault is
cleared. See Important note below.
If this fault occurs while the system is in the RUN mode, the controller faults. When expansion I/O
power is restored, the controller clears the fault and re-enters the RUN mode.
If you change the mode switch while this fault is present, the controller may not re-enter the RUN mode
when expansion I/O power is restored.
If an EPF condition is present and expansion I/O power is OK, toggle the mode switch to PROGRAM and
then to RUN. The fault should clear and the controller enters the RUN mode.
The program scan time exceeded the
watchdog timeout value (S:3H).
An error occurred in the STI
configuration.
Fault Recommended Action
Classification
• Either reset bit S:1/9 if this is consistent
Recoverable
with the application requirements, and
change the mode back to RUN, or
• clear S:1/13, the Major Error Halted bit,
before the end of the User Fault Routine.
Non-Recoverable Transfer the memory module program to the
controller and then change to Run mode.
• Upgrade the OS using ControlFlash to be
Non-User
compatible with the memory module.
• Obtain a new memory module.
• Contact your local Rockwell Automation
representative for more information about
available operating systems your
controller.
• Upgrade the OS using ControlFlash.
Non-User
• Contact your local Rockwell Automation
representative for more information about
available operating systems your
controller.
• Correct the instruction logic causing the
Recoverable
error.
• Enter the status file display in your
programming software and clear the fault.
• Enter the Run mode.
Non-User Re-apply power to the expansion I/O bank.
See Important note below.
• Determine if the program is caught in a
Non-Recoverable
loop and correct the problem.
• Increase the watchdog timeout value in
the status file.
Recoverable See the Error Code in the STI Function File for
the specific error.