What it means
The BMS detects deterioration in HV battery pack section C. Capacity or internal resistance outside service limits.
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 monitors high-voltage battery sections individually, and this code points to section C. It checks section C's capacity, internal resistance, and balance against service limits. P0EE0 is set when section C's monitored condition falls outside those limits.
Common causes
Most likely first.
- Cells aged - capacity reduced
- Internal resistance increased
- Pack cell imbalance approaching service threshold
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
- Record freeze-frame data and read section C capacity, resistance, and cell-balance values from the battery management system.
- Compare section C with adjacent battery sections during the same charge and load conditions to check whether the abnormality is specific to C.
- Inspect the battery cooling path and accessible section C connectors for restricted airflow, heat damage, corrosion, or looseness under the prescribed high-voltage safety procedure.
- Review section C temperature and sensing values for inconsistencies that could indicate a sensor or wiring issue.
- Use the manufacturer's battery evaluation procedure to determine whether section C cells have degraded or the monitoring circuit is inaccurate.
Common fixes
- Clear a confirmed obstruction in the battery cooling path.
- Repair damaged section C sensor wiring or connector contacts.
- Replace a failed sensing component if testing isolates the fault to it.
- Repair or replace the battery section or pack if section C deterioration is confirmed.
Can I keep driving?
Reduced power or limp operation can make merging and climbing less predictable, so limit driving to necessary trips and avoid heavy loads. Arrange prompt diagnosis if charging is slow or fails, and stop if power loss becomes severe.
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.