What it means
The high-voltage service disconnect circuit reports a open condition. Safe HV disconnection state cannot be verified.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
The service disconnect separates the traction battery from the vehicle's high-voltage system, while a low-voltage circuit tells the control module whether the disconnect is in its operating position. This code indicates the monitoring circuit is open, which may mean the disconnect is in its service position or a wire in that circuit has broken or become disconnected.
Common causes
Most likely first.
- Service disconnect switch in service position
- Open in disconnect wire
Symptoms
- Hybrid-system warning light may illuminate
- Vehicle may limit or disable hybrid operation
- Vehicle may fail to enter or remain in ready mode
How to diagnose it
- Record freeze-frame data and scan related hybrid codes to see whether the open condition appeared after service or during startup.
- Check the owner's manual and visually verify that the service disconnect is in its normal operating position; do not remove, reseat, or handle it unless the manual explicitly directs the owner to do so.
- With the vehicle powered down, inspect accessible low-voltage disconnect-circuit connectors and wiring for a disconnected plug, broken wire, or damage.
- Use the manufacturer's wiring diagram and procedure to test continuity through the disconnect monitoring circuit.
- If the wiring is intact, have a qualified hybrid technician determine whether the switch is open or faulty.
Common fixes
- Have the service disconnect returned to its normal operating position using the manufacturer's procedure if it was left in service position.
- Reconnect a loose low-voltage monitoring connector if accessible and permitted by the owner's manual.
- Repair an open or damaged wire in the disconnect circuit.
- Replace a failed service disconnect switch after testing confirms it is open.
Can I keep driving?
Do not drive if the vehicle will not enter or remain in ready mode; arrange safe transport for diagnosis. The module cannot verify the disconnect state, and the service disconnect and high-voltage system should not be handled.
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.