What it means
The supply circuit for the hybrid battery contactor control reports a low condition. Contactor coils may not energise as expected.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
The hybrid battery contactors are heavy-duty switches that connect the high-voltage pack to the vehicle. The control module monitors the supply feeding their control circuit and sets P2C94 when it detects that supply below the expected range, so the contactor coils may not energize reliably.
Common causes
Most likely first.
- Supply wire shorted to ground
- Supply rail collapses under load
- 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 scan hybrid battery and powertrain modules for related supply, contactor, and cell-balance codes before clearing anything.
- Check live data for the contactor control supply and pack cell balance to see whether the low reading occurs with a particular operating condition or imbalance.
- With the vehicle powered down using the manufacturer's high-voltage safety procedure, inspect the contactor control supply wiring and connectors for damage, moisture, or a wire pinched against ground.
- Have a qualified technician test the supply circuit for a short to ground and measure whether its voltage collapses under the specified load.
- If wiring and supply tests pass, compare individual cell data and contactor operation with the manufacturer's diagnostic procedure.
Common fixes
- Repair damaged or chafed contactor control supply wiring.
- Clean and secure a loose or contaminated low-voltage connector.
- Repair a supply connection or source that drops under load.
- Address a pack cell imbalance if testing confirms it is contributing to the fault.
Can I keep driving?
Avoid relying on electric power or attempting long trips; reduced power, failed charging, or limp mode may occur. If the vehicle loses propulsion or displays a high-voltage system warning, stop somewhere safe and arrange service.
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.