What it means
The ECM detects a intermittent fault on the 14 volt power module current sensor b circuit. Reading cannot be used reliably for control.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
The 14-volt power module uses current sensor B to report current flow to the ECM, which relies on that reading to manage the low-voltage electrical system. This code sets when the sensor B signal or its circuit drops out or changes unpredictably, so the reading cannot be trusted consistently.
Common causes
Most likely first.
- Sensor connector not seated
- Noisy ground reference
- Connector with intermittent contact under vibration
Symptoms
- Check-engine or hybrid-system warning light on
- Charging-system warning light may come on
- Charging or 12-volt system performance may be affected
How to diagnose it
- Record freeze-frame data and check whether the fault occurred with vibration, a particular load, or a change in vehicle operation.
- Use a scan tool to watch the 14-volt power module current sensor B reading and related charging data for dropouts while the fault is present.
- Inspect sensor B's connector for incomplete seating, corrosion, moisture, damaged terminals, or signs of movement.
- Check the sensor B wiring and ground reference for chafing, loose connections, or damage that could cause an intermittent signal.
- With the vehicle safely powered down according to its service information, test the sensor B circuit and ground while gently moving the harness, comparing results with the manufacturer's specification.
Common fixes
- Reseat and secure the sensor B connector.
- Repair a loose, corroded, or damaged sensor B terminal.
- Repair wiring or ground-reference damage in the sensor B circuit.
- Replace the current sensor B if its signal remains intermittent with sound wiring and connections.
Can I keep driving?
Avoid relying on the vehicle for long trips if charging warnings, reduced electrical performance, or hybrid-system warnings appear; a poor current reading can interfere with 12-volt system control. Stop safely if power or electrical systems become unreliable, and follow the vehicle's hybrid-system safety instructions.
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.