What it means
The high-voltage service disconnect circuit reports a circuit high 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 high-voltage service disconnect is monitored through a low-voltage circuit so the control module can verify its state. This code sets when that circuit reads higher than expected, which can occur if the wire is shorted to battery positive, the switch is open, or connector resistance disrupts the signal.
Common causes
Most likely first.
- Wire shorted to B+
- Switch open
- Connector pins corroded - high contact resistance
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 establish when the disconnect circuit high condition was detected.
- Check the owner's manual and confirm the service disconnect is fully in its normal operating position without removing it.
- With the vehicle powered down, inspect accessible low-voltage circuit wiring for contact with a power feed and connectors for corrosion, looseness, or damaged pins.
- Following the manufacturer's wiring diagram, test the disconnect monitoring circuit for a short to battery positive and check the switch signal.
- If no wiring short is found, have a qualified hybrid technician test for an open switch and high-resistance connector contact.
Common fixes
- Repair low-voltage disconnect-circuit wiring shorted to battery positive.
- Repair corroded or loose connector pins causing an unreliable signal.
- Replace a service disconnect switch confirmed open or faulty.
- Verify the module recognizes the disconnect state and confirm the code stays cleared.
Can I keep driving?
Do not drive if the vehicle cannot enter or remain in ready mode or hybrid operation is restricted; arrange safe transport. The system cannot verify the high-voltage disconnect state, so leave the disconnect and its wiring untouched.
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.