What Should I Check for JACK A4B Err-04 or Err-05 Overvoltage?
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: On the RA6/AHE59 220 V version, Err-04/Err-05 describe excessive supply voltage (manual threshold above 264 V).
What to do
- Identify the fitted controller and rated mains input, then have a qualified electrician verify the outlet supply and abnormal surge/incorrect circuit.
- Disconnect unsafe voltage and repair the branch circuit, regulator or connection as diagnosed.
Still not fixed? Continue to the next check.
↑ Back to the repair pathsB.
If the problem remains after the first checks
What this suggests: Do not copy those limits to 110 V A4B models.
What to do
- If the control reports overvoltage with independently correct supply, qualified service must inspect controller sensing and braking stages; do not replace the power board without confirmation.
Confirm the repair
No overvoltage code during idle, speed changes and braking at a correctly rated supply.