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 switch that tells the car to go faster when you press the gas pedal hard. It's like when you want to run faster, but your shoes are stuck.
The P278A code is triggered when the transmission control module (TCM) detects an issue with the kick down switch circuit, which is responsible for downshifting the transmission to provide more power when accelerating.
The kick down switch is part of the vehicle's transmission system. It signals the transmission to downshift when the accelerator pedal is pressed beyond a certain point. This code indicates a malfunction in the electrical circuit of this switch, which can affect the vehicle's ability to downshift properly.
• Reduced acceleration performance
• Transmission not downshifting properly
• Check Engine Light illuminated
• Faulty kick down switch
• Damaged or corroded wiring or connectors
• Faulty transmission control module (TCM)
Kick Down Switch: A switch that signals the transmission to downshift for increased acceleration.
Transmission Control Module (TCM): An electronic device that controls the transmission functions in a vehicle.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the kick down switch for proper operation.
• Replace the faulty kick down switch.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $500
Moderate
• Toyota Camry
• Honda Accord
• Ford Focus
• Regularly inspect and maintain transmission components.
• Keep wiring and connectors clean and free of corrosion.
• Ensure proper operation of the kick down switch during routine maintenance.
Sensor Issue
• Avoid hard acceleration until the issue is resolved.
• Get the vehicle inspected by a professional mechanic.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with vehicles that have had issues with their kick down switch due to wear and tear or electrical faults.
Moderate – While the vehicle can still be driven, performance may be affected, and further damage could occur if not addressed.
Driving with a malfunctioning transmission can be unsafe. Address the issue promptly to ensure vehicle safety.
• Vehicle at operating temperature
• Accelerator pedal fully depressed
The kick down switch is typically located near the accelerator pedal or integrated within the pedal assembly.
Q: Can I drive with a P278A code?
A: While you can drive with this code, it's not recommended as it may affect vehicle performance and could lead to further damage.
Q: How do I reset the P278A code?
A: After fixing the issue, you can reset the code using an OBD-II scanner. However, ensure the problem is resolved to prevent the code from returning.
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