failure mode

FM-21: FM-21 A NEW INTERNAL RATTLE OR LOOSE MOVEMENT IS HEARD AFTER IMPACT

FM-21

Diagnostic overview

FM-21

Likely Root Causes

  • An internal cell support or insulator broke
  • A power rail or electronic assembly loosened
  • A fastener or shell support failed internally
  • Impact damaged a cell connection without opening the shell

Quick Checks

  1. The rattling pack is not charged or used and is transferred only for approved replacement or recycling.

Repair Preview

1.

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

Related symptoms

  • The cool dry battery shell appears closed, but a new loose rattle, clunk or shifting movement is heard inside after a drop or impact, with no swelling, liquid, smoke, odor or heat.

    The cool dry battery shell appears closed, but a new loose 1. Remove the pack from every device and place it on a clear nonflammable surface.

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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