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 electrical connection where you plug in the charging cable. It's like when your game controller doesn't connect properly to your console.
The P1C91 code indicates an issue with the circuit that connects the charging station to the vehicle's charging interface. The signal voltage is higher than expected.
The P1C91 code is triggered when the vehicle's onboard diagnostic system detects a high voltage condition in the charging plug circuit of the loading interface module. This could be due to a malfunction in the charging plug, the wiring, or the module itself.
• Charging issues
• Warning light on dashboard
• Inability to charge the vehicle
• Faulty charging plug
• Damaged or corroded wiring
• Defective loading interface module
Charging Plug: The connector that links the charging station to the vehicle.
Loading Interface Module: The component that manages the electrical connection for charging the vehicle.
• Inspect the charging plug for damage.
• Check the wiring for signs of corrosion or damage.
• Test the loading interface module for proper operation.
• Replace the faulty charging plug.
• Repair or replace damaged wiring.
• Replace the loading interface module if defective.
• Multimeter
• Diagnostic scanner
• Basic hand tools
$200 - $500
Moderate
• Chevrolet Volt
• Nissan Leaf
• Tesla Model S
• Regularly inspect charging cables and plugs.
• Avoid exposing charging components to moisture.
• Ensure proper handling of charging equipment.
Electrical Circuit Issue
• Avoid charging in wet conditions.
• Regularly check the charging equipment for damage.
Check with your vehicle manufacturer for warranty coverage on electrical components.
This code has become more common with the rise of electric vehicles and increased reliance on charging infrastructure.
Moderate – Charging issues can prevent the vehicle from operating, but immediate action is not always necessary.
Ensure all repairs are conducted by a qualified technician to prevent electrical hazards.
• Vehicle in park and powered off
• Charging station connected
The charging interface module is typically located near the vehicle's charging port.
Q: Can I still drive my car with this code?
A: Yes, but you may experience charging issues that could prevent you from recharging the vehicle.
Q: Is this a common problem?
A: It can occur in electric vehicles, especially if the charging equipment is not maintained properly.
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