failure mode

FM-13: FM-13 BATTERY RUNS A TOOL AT NO LOAD BUT SHUTS DOWN UNDER ORDINARY LOAD

FM-13

Diagnostic overview

FM-13

Likely Root Causes

  • Excessive internal resistance causes voltage sag
  • One weak cell group triggers protection
  • Contacts or power rails cannot carry normal current
  • The tool task or accessory is actually overloaded

Quick Checks

  1. The battery completes the matched ordinary task without protection shutdown, or repeatable load-only failure is proven.

Repair Preview

1.

This is a preview of the troubleshooting guidance included in the full repair manual.

Common Fixes

  • Known-good compatible tool

Related symptoms

  • The pack starts and runs a known-good compatible tool at no load, but output stops promptly during an ordinary matched task that a known-good battery completes.

    The pack starts and runs a known-good compatible tool at no 1. Stop the task when output cuts off and remove the pack; inspect for unusual heat,

Included in the full manual

  • root cause analysis
  • tools needed
  • step-by-step repair procedure
  • diagrams
  • exploded views
  • post-repair checks

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