P0A20: Motor Torque Sensor Circuit High

What it means

The drive motor torque sensor reports a circuit high fault. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.

At a glance

• Usually lights the check-engine light
• The engine or gearbox may go into limp mode

How it works

The drive motor torque sensor provides feedback about torque produced by the traction motor. The control system sets this code when the sensor circuit signal is higher than the expected range, which can happen if the signal is shorted to power or the sensor circuit is open.

Common causes

Most likely first.

1. Signal wire shorted to B+
2. Open sensor
3. Connector pins corroded - high contact resistance

Symptoms

• Hybrid system or check-engine warning light on
• Reduced hybrid power or acceleration
• Possible rough or inconsistent power delivery

How to diagnose it

1. Save freeze-frame data and compare the drive motor torque sensor reading with commanded motor operation to confirm the high signal condition.
2. Inspect the torque sensor connector and harness for chafing, water entry, pushed-back pins, or corrosion.
3. With the circuit identified from vehicle service information, check for a signal wire short to power and verify the sensor's reference and ground circuits.
4. Check continuity and connector contact quality against the manufacturer's specification, paying attention to corroded pins that can distort the signal.
5. If wiring and circuit supplies test correctly, test the drive motor torque sensor according to the manufacturer's procedure.

Common fixes

• Reconnect and secure a poorly seated torque sensor connector.
• Repair damaged wiring or a signal wire short to power.
• Clean or replace corroded terminals and restore proper pin contact.
• Replace the drive motor torque sensor if its circuit output remains high after wiring checks.

Can I keep driving?

Because the high torque signal can cause reduced or inconsistent hybrid power, avoid hard acceleration and overtaking. If power delivery becomes unpredictable or the vehicle enters limp mode, stop safely and arrange diagnosis.