Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with the fan that helps cool the battery. The fan might be getting too much power or is not working properly.
The P0A85 code indicates that there is an issue with the electrical circuit controlling the cooling fan for the hybrid or electric vehicle's battery pack. The circuit is registering a higher than expected voltage.
The P0A85 code is triggered when the Powertrain Control Module (PCM) or Battery Energy Control Module (BECM) detects a high voltage condition in the control circuit of the battery pack cooling fan 1. This could be due to a short circuit, a faulty fan motor, or a problem with the control module.
• Check Engine Light is on
• Battery overheating
• Reduced vehicle performance
• Faulty cooling fan motor
• Short circuit in the wiring
• Defective control module
PCM: Powertrain Control Module
BECM: Battery Energy Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the cooling fan and wiring for damage.
• Test the fan motor and control circuit for proper operation.
• Replace the cooling fan motor if faulty.
• Repair or replace damaged wiring or connectors.
• Replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect cooling fan and wiring.
• Ensure proper ventilation for the battery pack.
• Schedule routine maintenance checks.
Electrical Circuit Issue
• Avoid driving in extremely hot conditions until fixed.
• Monitor battery temperature closely.
• Seek professional repair services.
Check with the vehicle manufacturer for warranty coverage on hybrid/EV components.
This code has become more common with the increase in hybrid and electric vehicle use, highlighting the importance of battery cooling systems.
Moderate – It is important to address this issue to prevent battery damage.
Ignoring battery cooling issues can lead to overheating, which may cause safety risks or reduce battery life.
• Vehicle must be in a safe and stable condition.
• Ensure the battery is at a normal operating temperature.
The cooling fan is typically located near the hybrid/EV battery pack, often in the rear of the vehicle.
Q: Can I drive with a P0A85 code?
A: It's not recommended to drive for long periods as it may cause battery overheating.
Q: How do I reset the P0A85 code?
A: After repairs, use an OBD-II scanner to clear the code, or disconnect the battery for a few minutes.
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