Why Does My JACK A4B Show Err-07 After Starting?
Exact model: JACK A4B-A/C
Safety: Disconnect mains before clearing thread or checking motor/solenoid connections.
A.
Start with the accessible checks
What this suggests: Err-07 is described as a current-measurement/feedback abnormality in the corresponding RA6 control manual, rather than a reason to alter sewing speed presets.
What to do
- Check and document the controller type first.
- Isolate mains, inspect motor/control plugs for loose pins, damaged cable and water intrusion, and ensure the sewing mechanism is not mechanically locked.
Still not fixed? Continue to the next check.
↑ Back to the repair pathsB.
If the problem remains after the first checks
What to do
- Where the machine runs freely and the fault persists, the RA6 service state monitor can help a qualified repairer examine current measurement against the exact board revision; no verified universal probe point or board repair value is available for all A4B variants.
Confirm the repair
The motor starts and stitches without Err-07 and without abnormal cable or controller heating.