What it means
The control module monitors actuator supply voltage B and sets this code when it detects an open circuit or loss of continuity in that supply path.
At a glance
- Usually lights the check-engine light
How it works
Actuator supply B is a power feed used by one or more engine actuators, with the control module checking whether that feed remains connected. This code sets when the module detects a break in continuity on the B supply path, such as a blown fuse or broken wire from the main relay.
Common causes
Most likely first.
- Blown fuse on the supply rail
- Broken supply wire from main relay
Symptoms
- Check-engine light
- One or more actuators may not operate
How to diagnose it
- Use a scan tool to record freeze-frame data and check which actuator-related faults are stored alongside P2669, since they can identify what lost power.
- Inspect the actuator supply B fuse and its terminals for a blown element, heat damage, or poor contact.
- With the wiring diagram, trace the B feed from the main relay and inspect for broken, loose, or damaged wires and connectors.
- Check for continuity through the supply path with power isolated as directed by the manufacturer, and locate any open section.
- If the feed and fuse are intact, verify relay output and module-side supply monitoring against the manufacturer's diagnostic procedure.
Common fixes
- Replace a blown actuator supply B fuse after checking for a short or overload.
- Repair a broken wire or damaged connection between the main relay and the B supply rail.
- Repair or replace a faulty main relay or its connector if it fails to deliver the supply.
Can I keep driving?
The check-engine light may be the only obvious sign, but one or more actuators may stop working. Avoid demanding driving if the engine runs poorly or responds unpredictably, because the affected actuator function may be unavailable.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.