P0A98: Hybrid/EV Battery Pack Cooling Fan 2 Stuck On

What it means

The control module detects that battery cooling fan 2 remains on when it should be off. It sets the code when fan operation does not match the control command.

How it works

Battery cooling fan 2 helps remove heat from the hybrid or EV battery pack when the control module requests airflow. This code sets when the module detects that fan 2 continues running after it has commanded the fan off.

Common causes

Most likely first.

1. Fan relay or control circuit stuck on
2. Faulty fan control module
3. Shorted fan wiring
4. Faulty fan feedback circuit

Symptoms

• Cooling fan runs continuously
• Hybrid system warning light
• Unusual fan noise

How to diagnose it

1. Record freeze-frame data and compare fan 2 command with its reported status to confirm the fan is staying on when not requested.
2. After allowing the vehicle to shut down normally, listen for whether fan 2 continues running and note whether it stops after the vehicle's normal cooling period.
3. Inspect fan 2's accessible wiring and connectors for damage or a short that could keep the fan energized.
4. Check the fan relay or switching circuit, where fitted, for contacts that remain closed after the off command.
5. If wiring and switching components check out, have the fan control module and feedback circuit tested against the manufacturer's procedure.

Common fixes

• Repair shorted or damaged fan 2 wiring.
• Clean or repair a corroded or loose fan 2 connector.
• Replace a relay with contacts that remain closed, if the vehicle uses a separate relay.
• Repair or replace the fan control module if it keeps fan 2 powered without a command.

Can I keep driving?

A fan that runs continuously can drain the low-voltage battery and may signal a control fault affecting battery cooling. Arrange diagnosis soon, especially if the hybrid-system warning appears, and avoid disconnecting high-voltage battery components.