Internal bus interrupted after I/O module n (Fault code 4, argument n)

What does I/O-LED 4-n* mean?

The internal bus communication is interrupted immediately after the nth I/O module in the node. This means that all modules physically located after module 'n' are not communicating with the Fieldbus Coupler. The specific module 'n' can be identified by the number of blink pulses on the I/O LED.

• Defective I/O module 'n' causing a break in the internal bus communication path
• Faulty connection, loose terminal, or missing termination module after module 'n'

Click steps to track your progress.

1. 1

   Switch off the supply voltage of the coupler.

2. 2

   Replace the nth module, as indicated by the blink code.

3. 3

   Switch the supply voltage on again to restart the coupler and verify bus integrity.