failure mode

FM-10: FM-10 CHARGER REPORTS FULL, BUT THE BATTERY HAS ALMOST NO USABLE ENERGY

The charger indicates a full charge, but the battery holds almost no usable energy and runs tools only briefly or not at all.

Diagnostic overview

The charger indicates a full charge, but the battery holds almost no usable energy and runs tools only briefly or not at all.

Likely Root Causes

  • A cell group cannot accept or retain charge
  • The protection circuit is reporting completion incorrectly
  • An internal connection opens after charging
  • The charger has a false-completion fault

Quick Checks

  1. The pack stores and delivers useful energy after a normal full indication, or repeatable false-full storage failure is proven.

Repair Preview

1.

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

Related symptoms

  • A proven compatible charger gives its normal full-charge indication, yet the removed battery shows little or no charge and can run a known-good low-load tool only briefly or not at all.

    A proven compatible charger gives its normal full-charge 1. Remove the pack after the full indication, let it rest briefly, and press the

Included in the full manual

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

Public pages show a preview only. Purchase the full manual to download complete repair steps, diagrams, and verification procedures.

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