P0A30: Drive Motor B Temperature Sensor Circuit

What it means

A fault is detected in the drive motor B temperature sensor circuit. The code identifies a circuit fault; the specific cause depends on the vehicle.

At a glance

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

How it works

Drive Motor B has a temperature sensor circuit that lets the control module monitor winding heat. P0A30 sets when the module detects an electrical fault in that specific sensor circuit, leaving it without a dependable Drive Motor B temperature signal.

Common causes

Most likely first.

1. Sensor failed
2. 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

1. Record freeze-frame data and check Drive Motor B temperature live data for a missing, fixed, or implausible reading.
2. Power down the vehicle using the manufacturer's procedure, then inspect the Drive Motor B sensor wiring and connectors for damage, looseness, or corrosion.
3. Check the sensor circuit for continuity and shorts using the manufacturer's test procedure.
4. Compare sensor and circuit measurements with the manufacturer's specification to locate a wiring or sensor fault.
5. If the circuit tests correctly, check the associated control-module connections and input.

Common fixes

• Reconnect a loose Drive Motor B temperature sensor connector.
• Clean corroded pins or repair damaged sensor wiring.
• Replace the Drive Motor B temperature sensor if its circuit tests out of specification.
• Repair the control-module connection or input if testing isolates the fault there.

Can I keep driving?

Limit driving and avoid hard acceleration because the system may reduce torque or shut down if it cannot monitor Drive Motor B temperature. Stop if power drops or a hybrid/EV warning indicates a serious fault.