Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the car's electrical system that helps control the power. It's like a switch that isn't working right, and it's stuck in the 'on' position.
The P1C99 code indicates an issue with the high voltage contactor control circuit, specifically that the positive contactor driver circuit is experiencing a high voltage condition.
The Loading Interface Module (LIM) is responsible for managing the high voltage contactor control in hybrid and electric vehicles. The positive contactor driver circuit is part of this system, and a 'high' condition suggests that the circuit is receiving more voltage than expected, which could be due to a short circuit or a faulty component.
• Check Engine Light is on
• Vehicle may not start
• Reduced performance in hybrid/electric mode
• Faulty contactor control module
• Short circuit in the wiring
• Defective relay or switch
Contactor: An electrically controlled switch used for switching a power circuit.
Loading Interface Module: A component in hybrid/electric vehicles that manages high voltage contactor control.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the contactor control module for proper operation.
• Replace or repair damaged wiring.
• Replace the faulty contactor control module.
• Ensure all connections are secure and free of corrosion.
• OBD-II Scanner
• Multimeter
• Screwdriver set
$200 - $600
Moderate
• Chevrolet Volt
• Nissan Leaf
• Toyota Prius
• Regularly inspect and maintain electrical connections.
• Avoid exposure of electrical components to moisture.
• Schedule regular check-ups for hybrid/electric systems.
Electrical System Issue
• Do not attempt to drive the vehicle if it won't start.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle manufacturer as this may be covered under the powertrain or emissions warranty.
This code has been more prevalent with the rise of hybrid and electric vehicles, as they rely heavily on complex electrical systems.
High – This issue can prevent the vehicle from starting or operating properly.
Driving with this code active can lead to unexpected vehicle behavior, which may be unsafe.
• Vehicle in hybrid/electric mode
• Engine off and ignition on
The Loading Interface Module is typically located near the vehicle's battery pack or under the hood in the engine compartment.
Q: Can I drive my car with a P1C99 code?
A: It's not recommended as the vehicle might not start or could experience reduced performance.
Q: Is this a common issue?
A: It can occur in hybrid and electric vehicles due to their complex electrical systems.
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