The B&R 3UM161.6 is a universal mixed module from the 2005 series that provides four ±10 V analog inputs (14‑bit), three ±10 V analog outputs (12‑bit), fourteen 24 VDC digital inputs, and multiple 24 VDC or 10 mA digital outputs. Common failure points for this class include damaged input/output contacts from overvoltage, insulation breakdown in the 24 V supply lines, and firmware corruption that can lock the module into a fault state. First‑check diagnostics: verify the 24 V DC power rail is within spec and stable; inspect all analog and digital terminals for physical damage or corrosion; review any stored error codes via the B&R controller interface to identify input/output channel faults.[oss-gpt-20b]