I/O Bus Resource Failure

What does E2-2 mean?

A resource failure has occurred on the I/O bus module. This means a critical component or allocated resource within the module (e.g., memory, processing units, communication channels) has become unavailable or corrupted, leading to operational issues and potential loss of I/O control.

• Over-current condition on an I/O module's internal power rail (e.g., 5VDC or 3.3VDC).
• Hardware failure of an integrated circuit (e.g., ASIC, FPGA) on the I/O bus module.
• Firmware bug or corrupted configuration preventing proper resource allocation (e.g., buffer memory).
• Excessive electrical noise coupled into the I/O bus communication lines (e.g., RS485 or EtherCAT).
• Incompatible I/O module inserted into the bus backplane.

Click steps to track your progress.

1. 1

   1. Identify the specific I/O module reporting the error via the system diagnostic log (e.g., module in slot 3).

2. 2

   2. Power cycle the entire I/O rack or controller by removing and reapplying 24VDC.

3. 3

   3. Remove and re-seat the identified I/O module (e.g., IM153-2) in its slot.

4. 4

   4. Check the I/O bus module's diagnostic LEDs for specific error codes (e.g., 'SF' LED).

5. 5

   5. Measure the internal 24VDC and 5VDC supply voltages on the I/O bus module's backplane connector.

6. 6

   6. Replace the suspected I/O bus module with a new unit.