What it means
The HV battery temperature sensor P reports a range/performance fault. Cell-group temperature monitoring impaired on this channel.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Sensor P measures the temperature of one section of the high-voltage battery for the battery control module. This code sets when the signal is electrically plausible but its reported temperature or response does not behave as expected, which can happen if the sensor has drifted, aged, or is no longer mounted correctly against the monitored area.
Common causes
Most likely first.
- Sensor characteristic drifted
- Sensor mounting displaced
- Sensor element aged beyond calibration window
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
- Review freeze-frame data and compare Sensor P’s reading with nearby battery temperature sensors under similar conditions.
- Check Sensor P live data from a cold start and during normal warm-up for a reading that lags, changes implausibly, or differs consistently from adjacent sensors.
- With the vehicle shut down under the manufacturer’s high-voltage safety procedure, inspect Sensor P’s mounting and connector for displacement, looseness, corrosion, or harness damage.
- Check that the sensor is positioned to measure its intended battery section and that its wiring has no open or short condition.
- Test Sensor P’s response against the manufacturer’s specification and replace it if its characteristic has drifted beyond the allowed range.
Common fixes
- Secure Sensor P in its intended mounting position.
- Repair or clean a loose or corroded Sensor P connector and damaged wiring.
- Replace Sensor P if its temperature response is outside the manufacturer’s specification.
Can I keep driving?
The system may limit battery power or charging because Sensor P’s temperature response is not dependable. Keep driving gentle and limited if the warning is present, and stop safely if reduced power becomes severe or a battery warning escalates.
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.