Mitsubishi PLCs Troubleshooting & Procedures

Step-by-step procedures

• Mitsubishi MELSEC ERR LED — Module Diagnostics in GX Works3 — A lit or flashing ERR LED on a MELSEC FX5U or iQ-R CPU means a diagnosable fault. Use GX Works3 Module Diagnostics to read the exact error code and clear continuation errors without a power cycle.