APC Error Code Reference — All 5 Codes
Complete APC error code cheat sheet. All 5 fault codes with plain-English explanations and direct links to fix guides.
Use this page when your APC UPS, generator, or power equipment reports a fault or alarm. Start with the exact code, then open the fix guide for battery faults, overload conditions, transfer problems, and inverter or charger failures.
Tip: search the exact brand, model, and code together, for example "APC F01" or "APC overload alarm".
| Error Code | What It Means | Often a cheap fix? | Guide |
|---|---|---|---|
| APC Back-UPS Pro F01-F09 Fault Codes: Official Meanings, Beep Patterns, and Fixes | The official APC F01-F09 System Fault table for Back-UPS Pro, cross-checked against four Schneider Electric sources. F01 and F02 are the only codes with a published user action; F03-F09 are contact-support faults. Plus beep patterns, the 2-second fault reset, and the exact RBC part number per model. | — | Fix → |
| APC Back-UPS Pro F02 Error (On-Battery Output Short): Causes and the Fix That Works | APC Back-UPS Pro F02 means the UPS detected a short circuit on its output while running on battery. The published fix is load isolation: unplug every device from the Battery Backup outlets, restart, and reconnect one item at a time until the fault returns. | — | Fix → |
| APC Smart-UPS Error Codes: Complete Guide | APC Smart-UPS error codes and alarm diagnostics. LED codes, fault descriptions, and technician-level troubleshooting for APC UPS systems. | — | Fix → |
| APC Symmetra LX PowerView Alarm Messages: Complete Verified Troubleshooting Reference | Every PowerView display message on the APC Symmetra LX (4-16 kVA) from official APC Operations Manual 990-1546: start-up warnings, module failures, threshold alarms, bypass and general fault messages, each with APC's own corrective action. | — | Fix → |
| APC UPS Fault Codes & Errors: F01-F09, Beeps, LEDs | APC UPS fault codes decoded: Back-UPS Pro F01-F09, Smart-UPS Replace Battery and Overload LEDs, Symmetra F-faults, plus beep patterns and real fixes. | — | Fix → |