OBD Guide

B0128

DC/AC Converter A High Voltage Power Outlet B Circuit/Open

B0128 is an OBD-II diagnostic trouble code meaning: DC/AC Converter A High Voltage Power Outlet B Circuit/Open. Common causes: open circuit of the high-voltage converter, dc/ac converter malfunction. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Lack of power at high-voltage consumers
  • Multimedia devices or inverter do not work
  • Check Engine light comes on

Causes

  • Open circuit of the high-voltage converter
  • DC/AC converter malfunction
  • Poor contact in connectors
  • Wiring harness damage
  • Short circuit in the circuit

How to Fix

  1. Check the integrity of the high-voltage converter circuit
  2. Inspect connectors and contacts for oxidation
  3. Check the functionality of the DC/AC converter
  4. Visually inspect the wiring harness for damage
  5. Replace converter if necessary

Related codes

Error B0128 by Vehicle Brand

FAQ

What does the B0128 code mean?

B0128 is an OBD-II diagnostic trouble code that indicates: DC/AC Converter A High Voltage Power Outlet B Circuit/Open

What causes a B0128 error code?

The most common causes of B0128 include: Open circuit of the high-voltage converter; DC/AC converter malfunction; Poor contact in connectors; Wiring harness damage.

How do I fix a B0128 diagnostic trouble code?

To fix B0128: Check the integrity of the high-voltage converter circuit. Inspect connectors and contacts for oxidation. Check the functionality of the DC/AC converter. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B0128?

Limited driving only, diagnose soon

How much does it cost to fix B0128?

The estimated repair cost for B0128 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat