When a UPS system displays a battery warning, it’s time to act. Whether you’re running critical infrastructure, managing data continuity, or ensuring compliance with health and safety standards, ignoring UPS error messages can lead to costly downtime or system failure.
In this blog, we explain the most common UPS battery error codes and messages, what they mean, and what action you should take, with a focus on keeping your systems compliant, reliable, and operational.
1. UPS Error Message: “UPS Battery Needs Replacement”
What it means:
Your UPS system has detected that the internal battery has degraded beyond acceptable performance levels. This is typically based on charge retention, cycle history, or internal resistance thresholds.
Action required:
Arrange for a UPS battery replacement as soon as possible. Batteries in this state may not support the load during a power outage. BCL Power’s specialist technicians can assess the system and replace UPS batteries with minimal disruption.
2. UPS Error Message: “Battery Near End of Life. Order Replacement Battery”
What it means:
The system is giving you advance warning that battery capacity is declining – this message often appears months before total failure.
Action required:
Schedule proactive UPS battery maintenance or a full UPS battery replacement. Don’t wait until the battery fails completely. BCL Power can source and fit compatible APC UPS batteries or batteries for other major UPS brands.
3. UPS Error Message: “Replace Battery Soon” / “Battery Needs Attention”
What it means:
This is a general warning that the UPS has detected a loss of performance, possibly due to battery age, high temperatures, or repeated discharge cycles.
Action required:
Contact a UPS battery professional to inspect the system and confirm whether the issue is with the battery itself or another component. BCL Power offers full UPS system tests to diagnose and resolve issues before they cause downtime.
4. UPS Error Message: “UPS Internal Fault” or “UPS Fault”
What it means:
This may indicate a deeper issue that could involve battery faults, inverter errors, or control board problems.
Action required:
Do not attempt a DIY fix, these messages require a trained UPS maintenance specialist. BCL Power provides nationwide support with engineers qualified to diagnose and resolve system faults safely.
5. UPS Error Message: “Site Wiring Fault” (Common on APC UPS Devices)
What it means:
This warning suggests a wiring issue, such as reversed polarity or missing ground, which can impact UPS function and safety.
Action required:
While this isn’t a battery fault, it’s critical. Have a qualified UPS specialist inspect the site wiring and UPS input. BCL Power technicians are trained to identify and resolve installation issues.
6. UPS Error Message: “Overload”
What it means:
The connected equipment is drawing more power than the UPS can handle. This could affect runtime and cause the unit to shut down during a power cut.
Action required:
Review the load and consider reducing it or upgrading the UPS. BCL Power can help size and install a more suitable UPS system.
7. UPS Error Message: Specific Fault Codes (e.g. APC Code F06, Eaton Fault 113)
What it means:
Many UPS systems, especially larger models, display numeric fault codes. For example:
- APC F06 – Relay welding or charger fault
- Eaton 113 – Battery voltage fault
Action required:
Refer to the manufacturer’s manual, but always consult a UPS professional. BCL Power technicians are experienced in diagnosing fault codes across all major UPS brands.
Why It’s Critical to Act Quickly
- Battery failure is the #1 cause of UPS failure – Regular checks and prompt replacements are key to system reliability.
- Compliance matters – Under SFG20 maintenance standards, UPS systems must be maintained and tested on a scheduled basis.
- Unplanned downtime is expensive – A proactive approach to UPS maintenance protects business continuity, and cost-effective maintenance.
Need Support with UPS Battery Replacement or Maintenance?
BCL Power has over 30 years of experience helping businesses maintain UPS systems across the UK. Whether you’ve seen a warning on your APC UPS or need a full UPS system audit, our nationwide team of specialist technicians is ready to help.
Contact BCL Power today to book a battery replacement, UPS system test, or preventative maintenance visit.