The I/O Fault LED is red and indicates faults on I/O channels. The I/O Fault LED displays both a fault code and a channel code. You will first see a series of short flashes that indicate the fault type, then a series of long flashes that indicate the channel number.
Long flashes indicate channel number so that n + 1 flashes = channel n.
For example, a test pulse or readback fault on DO2 will cause the I/O Fault LED to display the following flash pattern: Two short flashes + pause + three long flashes
|Flashes continuously||An overcurrent fault has been detected.|
|Flashes two times then pauses||A test pulse or readback fault has been detected.|
|Flashes three times then pauses||A discrepancy fault has been detected.|
|Off||No I/O Fault has been detected.|