Faulty DC/AC converter (inverter) assembly internal high-voltage circuit.; Damaged or shorted high-voltage wiring between the converter and the power outlet.; Poor ground connection at the converter or outlet, causing voltage spikes.; Failed power outlet control module or BCM internal fault.; Corrosion or water intrusion in the power outlet or connector, leading to high resistance.; Aftermarket accessories improperly wired to the power outlet circuit.

DTC codes / B01xx · Airbags, seats, doors, lights and comfort systems / B012C

B012CDC/AC Converter A High Voltage Power Outlet Control Module "A"

B012C indicates that the body control module (BCM) has detected a high-voltage condition on the control circuit for power outlet converter A, which is the DC-to-AC inverter that provides household-style AC power to the vehicle's outlets. The BCM monitors the converter's high-voltage output and sets this code when the voltage exceeds the expected range, often due to a fault inside the converter or a wiring problem.

SystemBody

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaAirbags, seats, doors, lights and comfort systems

Symptoms you may notice

The AC power outlet stops working or delivers no power to connected devices.
The warning light or message for the power outlet system illuminates on the dashboard.
The inverter may shut down intermittently or fail to turn on at all.
A burning smell or visible damage may be noticed near the power outlet or converter.
Often no symptoms besides the warning light, especially if the outlet is not used.
Other low-voltage accessories may behave erratically if the converter is loading the electrical system.

Common causes, most likely first

Faulty DC/AC converter (inverter) assembly internal high-voltage circuit.
Damaged or shorted high-voltage wiring between the converter and the power outlet.
Poor ground connection at the converter or outlet, causing voltage spikes.
Failed power outlet control module or BCM internal fault.
Corrosion or water intrusion in the power outlet or connector, leading to high resistance.
Aftermarket accessories improperly wired to the power outlet circuit.

How to diagnose and fix it

Inspect the power outlet and converter for visible damage, corrosion, or loose connections.
Check the converter's ground connection and clean or tighten as needed.
Measure the high-voltage output at the outlet with a multimeter to confirm the overvoltage condition.
Disconnect the converter and inspect the wiring harness for shorts or chafing.
Substitute a known-good converter to see if the code clears.
If the converter is good, test the control module and wiring for faults.
Clear the code and verify the repair with a test drive and outlet load test.

High-Voltage Outlet Faults Often Misdiagnosed

A weak or failing 12-volt battery can cause the converter to boost voltage excessively, setting this code even when the converter itself is fine.
The code can be set by a momentary voltage spike during engine cranking, so always check for a low battery before replacing the converter.
Aftermarket phone chargers or inverters plugged into the outlet can back-feed voltage and trigger the code, so test with the outlet empty.
The BCM may set B012C if the converter's cooling fan fails, causing overheating and voltage regulation problems.
Water leaks into the rear quarter panel or cargo area often corrode the converter connectors, leading to this code on vehicles with rear-mounted outlets.

Can I keep driving with B012C?

You can usually drive the vehicle with this code, but avoid using the AC power outlet until the fault is repaired. If you notice a burning smell or smoke, stop driving and disconnect the battery to prevent a fire risk.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.