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 thinks the temperature sensor for the hybrid or electric battery is reading too high, like when a thermometer shows a number that's way too big.
The P0C84 code indicates that the vehicle's control module has detected a high voltage signal from the hybrid or electric vehicle battery temperature sensor H circuit.
The P0C84 code is triggered when the Powertrain Control Module (PCM) or Battery Energy Control Module (BECM) detects a voltage signal from the battery temperature sensor H circuit that is higher than the expected range. This may indicate an issue with the sensor itself, the wiring, or the control module.
• Check Engine Light is on
• Reduced fuel efficiency
• Possible overheating of the battery
• Faulty battery temperature sensor
• Wiring issues such as open or short circuits
• Faulty PCM or BECM
PCM: Powertrain Control Module
BECM: Battery Energy Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the battery temperature sensor for proper operation.
• Replace the faulty battery temperature sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM or BECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular maintenance of the hybrid/EV battery system.
• Ensure proper cooling of the battery.
• Check wiring and connectors for wear and tear.
Sensor Issue
• Do not ignore the check engine light.
• Have the vehicle inspected by a professional if you notice any symptoms.
• Avoid driving the vehicle aggressively until the issue is resolved.
Check with the vehicle manufacturer for warranty coverage on hybrid/EV components.
This code has been associated with issues in hybrid and electric vehicles as they age, particularly in models with high mileage.
Moderate – Address the issue soon to avoid potential battery damage.
Driving with a malfunctioning battery temperature sensor can lead to battery overheating and potential safety hazards.
• Vehicle must be in a safe environment.
• Battery should be at normal operating temperature.
The battery temperature sensor is typically located within or near the battery pack of the hybrid or electric vehicle.
Q: Can I drive with a P0C84 code?
A: It's not recommended to drive for extended periods with this code, as it may lead to battery overheating.
Q: How do I reset the P0C84 code?
A: After fixing the issue, use an OBD-II scanner to clear the code. If the problem persists, the code will return.
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