Siemens SINAMICS G120 Error Code F31156

Siemens PLC & VFD Major Encoder

Model: SINAMICS G120 | Code: F31156

Applicable Systems
S7-1200 S7-1500 S7-300 S7-400 LOGO! SINAMICS

Symptoms

Encoder open circuit: encoder circuit open detected.

Possible Causes

  • Encoder cable broken
  • Encoder connector loose
  • Encoder coil open

Troubleshooting Steps

  1. Step 1: Check encoder cable continuity
    Cable intact
  2. Step 2: Verify encoder connector
    Connector fully seated
  3. Step 3: Replace encoder if coil open
    New encoder operates correctly

How to Reset

Reset via operator panel after encoder open circuit is repaired.

Related Siemens Fault Codes

Source: Siemens SINAMICS G120 List Manual

Category: PLC & VFD