On a Brother home embroidery machine, the message “The safety device has been activated” typically indicates that the machine has detected a mechanical issue and has stopped to prevent damage. This is a protective feature built into many Brother embroidery/sewing machines. Here are the most common causes:
Common Causes and Fixes:
1. Thread Jam or Tangle
Cause:
Threads are stuck in the bobbin area or tangled under the needle plate.
Fix:
Remove the needle plate and bobbin case.
Clean out lint, broken thread, or jammed fabric.
Re-thread the machine from scratch (both top and bobbin).
2. Hook Race Is Jammed or Dirty
Cause:
Lint, thread, or debris is blocking the hook mechanism (the rotating part under the bobbin).
Fix:
Open the hook race cover and remove the bobbin case.
Clean the hook race thoroughly with a small brush or vacuum.
Reinsert the hook components carefully.
3. Needle Is Bent or Misaligned
Cause:
A bent or improperly inserted needle can hit the bobbin case or plate.
Fix:
Replace the needle with a new one.
Make sure it is fully inserted and facing the correct direction.
4. Thread Wrapped Around Motor Shaft
Cause:
Embroidery thread can get pulled into the motor shaft or behind the handwheel.
Fix:
Inspect the rear of the machine or under the handwheel.
If you see thread, do not force the machine—have it removed carefully (possibly by a technician).
5. Incorrect Threading or Tension
Cause:
Improper threading can cause tension issues that trigger a safety stop.
Fix:
Remove all thread.
Rethread both the upper thread and bobbin correctly, following your manual.
6. Something Hit the Needle (Like a Hoop or Foot)
Cause:
A thick area of fabric or hoop hit the needle or presser foot.
Fix:
Check that your hoop is installed properly and not hitting the foot.
Lower the presser foot before starting.
Make sure the design is not trying to stitch outside the hooped area.
7. Machine Needs to Be Reset
Fix:
Turn off the machine and unplug it.
Wait 10–30 seconds.
Plug the machine back in and turn it on.
If the Error Won’t Clear:
If you’ve cleared jams, cleaned the machine, and rethreaded everything but still get the message:
Try restarting with a new design and empty hoop.
If that doesn’t help, a service technician may need to inspect the internal gears or motor.