Hybrid Battery Pack Cooling Fan 2 Stuck On
The P0A98 code means the vehicle's onboard diagnostic system has detected: Hybrid Battery Pack Cooling Fan 2 Stuck On. This is a moderate severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- moderate
- Estimated cost
- $100 - $700 (relay or control fault at the low end; fan assembly at the high end)
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Common Symptoms
- Check Engine Light on
- Battery cooling fan running constantly, even with a cold pack or after shutdown
- Possible 12V battery drain from a fan that never stops
Probable Causes (Ranked by Likelihood)
- Stuck relay or shorted control circuit holding the fan on High
- Failed fan speed controller Moderate
- Module driver fault Moderate
Frequently Asked Questions
What does P0A98 mean?
P0A98 means the Hybrid Battery Pack Cooling Fan 2 is stuck on - running when the module has commanded it off.
Can I keep driving with P0A98?
Yes - a fan that will not stop cools the pack fine; the risks are annoyance and a drained 12-volt battery if it runs after shutdown. Repair soon but it is not urgent.
Is P0A98 safe to work on myself?
Cleaning the cabin-side battery cooling intake is generally owner-serviceable. Anything beyond that: This code involves the high-voltage system. Do not open the HV battery, inverter, or any orange-cabled component without hybrid-specific training, insulated gloves, and the service plug removed. Diagnosis beyond a scan-tool read belongs at a hybrid-qualified shop.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
-
Confirm the complaint: the fan should stop when the pack is cool and the vehicle is off.
-
Check the fan relay and control circuit for a short holding the fan energized.
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Watch for 12V battery drain if the fan runs after shutdown.
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Follow the OEM pinpoint test for the fan control circuit.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
Commonly Affected Vehicles
- Toyota Prius and other Toyota/Lexus hybrids
- 2005-2012 Ford Escape Hybrid / Mercury Mariner Hybrid
- Honda Insight and Civic Hybrid
- Hyundai Sonata Hybrid / Kia Niro Hybrid
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