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 is having trouble with the button or switch that helps your car save fuel. It's like when a remote control button isn't working right.
The P05C8 code is triggered when the vehicle's powertrain control module (PCM) detects an issue with the economy mode switch circuit, indicating that the circuit is not performing within the expected range.
The economy mode switch is part of the vehicle's system that allows the driver to select a mode of operation that prioritizes fuel efficiency. The PCM monitors the switch's circuit for proper voltage and functionality. If the circuit's performance is outside the expected parameters, the P05C8 code is set.
• Check Engine Light is on
• Economy mode not engaging
• Reduced fuel efficiency
• Unresponsive economy mode button
• Faulty economy mode switch
• Wiring issues in the switch circuit
• Defective PCM
• Corroded or damaged connectors
PCM: Powertrain Control Module, the computer that controls engine and transmission functions.
Economy Mode: A setting in some vehicles that prioritizes fuel efficiency over performance.
• Use an OBD-II scanner to confirm the code.
• Inspect the economy mode switch for physical damage.
• Check the wiring and connectors for corrosion or damage.
• Test the switch circuit for proper voltage and continuity.
• Replace the faulty economy mode switch.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• Clear the code and test the system.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $300
Moderate
• Toyota Camry
• Honda Accord
• Ford Fusion
• Regularly inspect and maintain vehicle wiring.
• Avoid exposure of electrical components to moisture.
• Use the economy mode switch as intended.
Sensor Issue
• Avoid using the economy mode until the issue is resolved.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle manufacturer for warranty coverage on electrical components.
This code is relatively uncommon and typically associated with vehicles that offer an economy mode feature.
Moderate – While not critical, addressing this issue can improve fuel efficiency.
Driving with a malfunctioning economy mode switch is generally safe, but it may lead to reduced fuel efficiency.
• Vehicle in park and engine running.
• Economy mode switch engaged.
The economy mode switch is usually located on the dashboard or center console.
Q: Can I drive my car with the P05C8 code?
A: Yes, but your car may not be as fuel-efficient as it could be.
Q: Will this code affect my car's performance?
A: It may reduce fuel efficiency but should not affect overall performance.
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