What it means
The high-voltage interlock circuit of battery charging system B reports a circuit low condition. Safety interlock chain may be compromised.
At a glance
- Usually lights the check-engine light
How it works
Battery charging system B's high-voltage interlock is monitored as part of the vehicle's safety chain. This code sets when the module detects the interlock signal below its expected range, which can result from an interrupted signal or poor electrical contact such as corrosion at a connector.
Common causes
Most likely first.
- Interlock signal interrupted
- Interlock connector not seated
- Connector pins corroded - high contact resistance
Symptoms
- Check-engine or hybrid-system warning light
- Charging may be disabled
- Hybrid or electric drive may be limited or unavailable
How to diagnose it
- Review freeze-frame data and related codes to confirm the fault is on charging-system B's interlock and note whether charging was active.
- With the vehicle powered down, inspect accessible interlock B connectors for incomplete seating, moisture, or corroded pins.
- Check accessible harness sections for chafing, crushing, or a signal wire contacting ground, without opening high-voltage components.
- Use scan-tool live data and manufacturer-approved tests to confirm the interlock signal remains low and identify the affected segment.
- Have connector contact and circuit continuity checked to the manufacturer's specification using the prescribed high-voltage safety procedure.
Common fixes
- Correctly seat a loose accessible interlock connector.
- Repair damaged wiring that is shorted to ground.
- Repair or replace corroded terminals or connectors.
- Replace a confirmed faulty interlock component.
Can I keep driving?
Charging may be disabled and electric drive may be limited because the vehicle cannot confirm the interlock chain. Do not bypass or handle high-voltage connections; arrange qualified service if the warning persists or drive is restricted.
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.