Missing Process Voltage (UP or UP3)

What does E4-16173 mean?

The required process voltage (UP or UP3) for the I/O bus module is not present. This critical power supply issue will prevent the I/O module and any connected field devices from operating correctly, resulting in a complete loss of I/O functionality.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Ensure the power supply unit itself is functioning correctly and delivering the expected voltage.

2. 4

   Inspect the module's power input terminals for loose connections.