Logic Error: Error in an input or output module

What does flickering mean?

When LED Diag 1 is lit and LED Diag 2 flickers (50 ms ON / 50 ms OFF), it indicates an error specifically within an input or output module. This suggests a malfunction at the physical interface where signals are read or controlled. The specific input or output module affected is not specified by the flickering pattern alone, requiring further investigation.

• Faulty input module signal integrity.
• Erroneous signal from a connected digital input sensor.
• Faulty output module response.
• Short circuit or open circuit on an I/O terminal.
• Internal logic error within the I/O processing unit.

Click steps to track your progress.

1. 1

   Measure voltage at the specific input terminal (e.g., DI1) when the sensor is activated.

2. 2

   Inspect the wiring of the affected input/output module for physical damage.

3. 3

   Verify the state of the input module via diagnostic parameter (e.g., P2-01) and compare with physical sensor state.

4. 4

   Test the output module by commanding it via a diagnostic function and measure voltage at the output terminal.

5. 5

   Isolate the I/O module by disconnecting external wiring and observe fault behavior.