| LED | Correct Operating Condition | Fault Indication | Possible Cause | Corrective Action |
|---|---|---|---|---|
| Green - Power | On | Off | 1. Power is not supplied to unit. | 1. Check supply power and connections. |
| 2. Internal fault. | 2. Contact technical support. | |||
| Red - Error | Off | On (continuous) | Communications error. | Check connections, cable, and external device. |
| Flashing | Address conflict. | Replace card with known good card of same type; contact technical support. |