What it means
The BMS detects a circuit low fault on voltage sense channel P of the high-voltage battery. Cell-group voltage measurement is unreliable on this channel.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
The battery management system measures the voltage of a cell group through sense channel P to track the high-voltage battery. This code sets when the channel's signal is below the expected range, so the module cannot rely on that cell-group reading.
Common causes
Most likely first.
- Sense wire shorted to ground
- Open in sense wire
- Connector pins corroded - high contact resistance
Symptoms
- EV/hybrid system warning light on
- Reduced power output or limp mode
- Charging may fail or be slowed
- Reduced electric range
How to diagnose it
- Save freeze-frame data and compare live channel P voltage with nearby cell-group readings to see whether the signal is persistently low.
- With the vehicle powered down as specified by the manufacturer, inspect channel P wiring and connectors for damage, corrosion, or a pin pushed out of place.
- Have a qualified hybrid technician check the channel P sense wire for a short to ground or an open using the manufacturer's isolation and test procedures.
- Check connector contact resistance and continuity against the manufacturer's specification, since a poor connection can pull the reading low.
- If wiring and connections pass, test the battery monitoring module and its channel P input according to the manufacturer's diagnostic procedure.
Common fixes
- Repair damaged channel P wiring or insulation that is shorted to ground.
- Restore an open in the channel P sense wire.
- Clean or repair corroded channel P connector terminals and ensure a secure connection.
- Repair or replace the battery monitoring module if its channel P input is faulty.
Can I keep driving?
Avoid relying on electric power or taking long trips; reduced power or a failed charge may leave the vehicle unable to operate as expected. Because the battery reading is unreliable and the system may enter limp mode, arrange prompt diagnosis by a qualified hybrid technician.
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.