What it means
The BMS detects that battery pack subsection C is operating above the safe temperature threshold. Cell-level cooling or pack thermal management is compromised on this section.
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 temperature in hybrid/EV battery pack subsection C and compares it with the pack's safe operating limit. P2D47 sets when subsection C is too hot, potentially because cooling flow is reduced there, cells are imbalanced and heating locally, or its ground connection has excessive resistance.
Common causes
Most likely first.
- Coolant flow to this section reduced
- Cell imbalance causes local heating
- Ground point with elevated 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
- Record freeze-frame data and compare subsection C temperature with other pack sections, battery load, and cooling commands.
- Check whether the temperature rise is concentrated in subsection C or follows heavy driving or charging.
- Inspect accessible cooling paths, hoses, and connections serving subsection C for blockage, leaks, or loose connections, following high-voltage safety procedures.
- Review scan-tool cell voltage and temperature data for imbalance or a subsection C sensor reading that differs from adjacent areas.
- Have the subsection C ground path and battery thermal management tested to the manufacturer's procedure if basic checks do not explain the heat.
Common fixes
- Clear a confirmed blockage or restore coolant flow to subsection C.
- Repair a leak or damaged cooling connection serving subsection C.
- Repair a high-resistance ground connection if testing confirms it is responsible.
- Service the pack if cell imbalance or a failed temperature sensor is confirmed.
Can I keep driving?
Avoid driving and charging if the vehicle reports a battery over-temperature warning; stop safely and follow the vehicle's instructions. Continued heat in subsection C can cause severe power limitation and damage the high-voltage battery.
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.