What it means
The ECM detects a circuit fault on the hybrid/ev battery temperature sensor c circuit. Reading cannot be used reliably for control.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Battery temperature sensor C measures temperature at one location in the hybrid or EV battery pack, and the battery control system uses it to manage charging, cooling, and power. This code sets when the sensor C circuit has an electrical fault that makes its temperature reading unreliable.
Common causes
Most likely first.
- Fault in temperature-sensor wiring or connector
- Failed battery temperature sensor C
- Fault in the battery control module
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
- Use a scan tool to record freeze-frame data and compare sensor C with the other battery temperature readings for an implausible value.
- Inspect the accessible sensor C connector and wiring for damage, loose fit, corrosion, or pin problems.
- Check the sensor C circuit for continuity and shorts using the vehicle wiring diagram and manufacturer's procedures.
- If the wiring and connector check out, test sensor C against the manufacturer's specification.
- If the sensor and circuit pass, check for battery control module faults and related codes before considering module diagnosis.
Common fixes
- Reconnect or repair a loose or damaged sensor C connector.
- Repair damaged sensor C wiring.
- Replace a failed battery temperature sensor C.
- Repair or replace the battery control module if testing confirms its fault.
Can I keep driving?
Avoid hard acceleration, heavy loads, and fast charging; the vehicle may limit power or charging because it cannot rely on sensor C to assess battery temperature. If a hybrid or EV warning appears with reduced power or abnormal battery heating, stop safely and arrange prompt diagnosis.
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.