What it means
The position sensor channel B of drive motor A reports a circuit fault. Phase commutation feedback 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
Drive Motor A uses a position sensor to tell the hybrid or EV control module where the motor rotor is as it turns. The module monitors channel B's electrical signal and sets P0C5A when that channel has a circuit fault that prevents reliable commutation feedback.
Common causes
Most likely first.
- Position sensor failed
- Wiring fault
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Read freeze-frame data and related hybrid or EV codes to see when the Drive Motor A channel B fault occurred and whether other sensor or supply faults are present.
- Check live data for Drive Motor A position sensor channel B and compare its reported behavior with other available motor position data.
- With the vehicle powered down according to the manufacturer's safety procedure, inspect the channel B sensor connector and harness for damage, loose fit, corrosion, or chafing.
- Check the sensor's power and ground connections and test continuity of the channel B signal wiring using the manufacturer's procedure.
- If wiring and connections pass, test Drive Motor A's position sensor channel B against the manufacturer's specification before replacing it.
Common fixes
- Reseat and secure the Drive Motor A position sensor connector.
- Repair damaged or chafed channel B wiring and restore any poor connections.
- Clean or repair corroded connector terminals.
- Replace the Drive Motor A position sensor if its channel B circuit fails the specified test.
Can I keep driving?
Because the fault can reduce motor torque or trigger limp mode or shutdown, avoid relying on the vehicle for longer trips or situations where loss of propulsion would be hazardous. If power is reduced or the warning appears with abnormal operation, 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.