What it means
The hybrid control module detects a generic fault on phase Z current measurement of drive motor A. The drive motor's position, current and temperature are watched continuously; a fault here downgrades the inverter to a safe operating point or triggers torque reduction.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Drive motor A has a phase Z current sensor that helps the inverter regulate torque and lets the hybrid control module monitor motor operation. This code indicates a general fault in the phase Z current measurement, without specifying that the reading is low or high, and the module may limit torque.
Common causes
Most likely first.
- Phase current sensor failed
- Wiring or connector fault
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Save freeze-frame data and compare live drive motor A phase Z current with phases X and Y under the same conditions.
- Review related hybrid, inverter, and motor codes for clues about a shared power, ground, or measurement problem.
- With the vehicle powered down according to the manufacturer's safety procedure, inspect the phase Z sensor connector and wiring for corrosion, looseness, moisture, or physical damage.
- Check the phase Z sensor supply, ground, signal, and wiring continuity using the manufacturer's procedure.
- If the wiring is intact, test the phase Z sensor and inverter measurement circuit against the manufacturer's specification.
Common fixes
- Secure or clean the phase Z sensor connector.
- Repair damaged phase Z sensor wiring.
- Replace a failed phase Z current sensor if separately serviceable.
- Repair or replace the inverter if its phase Z measurement circuit is faulty.
Can I keep driving?
Drive gently and avoid relying on full hybrid power because the system may reduce torque or enter limp mode. Stop safely if power drops sharply or the vehicle warns of a hybrid-system shutdown.
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.