P0A35: Drive Motor B Over Temperature

What it means

Drive motor B temperature has exceeded the monitored limit. The code indicates an over-temperature condition; the 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 produces or transmits propulsion torque and generates heat under load; its temperature monitoring lets the hybrid control system protect the motor. P0A35 sets when the monitored temperature exceeds the allowed limit, which can result from a cooling fault or sustained heavy motor demand.

Common causes

Most likely first.

1. Motor cooling system failure
2. Sustained high motor load

Symptoms

• EV/hybrid system warning light on
• Reduced motor power or torque
• Possible limp mode or vehicle shutdown

How to diagnose it

1. Check freeze-frame data and live drive motor B temperature, along with the load and speed conditions present when the code set.
2. Inspect the drive motor B cooling path for visible leaks, blocked airflow or passages, damaged hoses, or other signs of a cooling-system problem specific to the vehicle.
3. Check the applicable cooling pumps, fans, and circulation indications using the manufacturer's procedure to see whether heat is being carried away from drive motor B.
4. If the temperature reading or cooling operation seems inconsistent, test the motor temperature sensor and related circuit against the manufacturer's specification.
5. Correct the cause, allow the system to cool as specified, clear the code, and verify temperature remains controlled under moderate operating conditions.

Common fixes

• Restore the specified cooling flow by repairing a leak, blockage, or failed cooling component serving drive motor B.
• Repair or replace a failed motor cooling pump or fan if confirmed by testing.
• Reduce sustained high-load use that is overheating drive motor B while the cooling system is checked.
• Replace a faulty temperature sensor or repair its circuit only if testing shows the reported heat is inaccurate.

Can I keep driving?

Do not continue driving under heavy load or if the hybrid system warns of overheating; stop safely and let the vehicle cool according to its instructions. Continued operation can force reduced power or shutdown and may damage drive motor B.