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 a switch that helps the car speed up quickly when you press the gas pedal hard.
The kick down switch is part of the transmission system that helps the car downshift when you press the accelerator pedal quickly. This code indicates a problem with the electrical circuit of this switch.
The P278C code is triggered when the Powertrain Control Module (PCM) detects a low voltage condition in the kick down switch circuit. This switch is used to signal the transmission to downshift to a lower gear for increased acceleration when the throttle is rapidly applied.
• Poor acceleration
• Transmission not downshifting properly
• Check Engine Light illuminated
• Faulty kick down switch
• Damaged or corroded wiring or connectors
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Inspect the kick down switch and its wiring for damage.
• Check for corrosion or loose connections in the circuit.
• Test the switch operation using a multimeter.
• Replace the faulty kick down switch.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• Multimeter
• Screwdriver set
• OBD-II scanner
$100 - $300
Moderate
• Toyota Camry
• Honda Accord
• Ford Fusion
• Regularly inspect wiring and connectors for damage.
• Keep the transmission system well-maintained.
• Avoid aggressive driving habits.
Sensor Issue
• Drive smoothly to avoid triggering the issue.
• Schedule a diagnostic check with a mechanic.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with vehicles that experience transmission issues due to faulty switches or wiring problems.
Moderate – Address the issue soon to avoid potential transmission damage.
Driving with a malfunctioning transmission system can be unsafe and may lead to further damage.
• Vehicle at operating temperature
• Accelerate rapidly to test the kick down function
The kick down switch is typically located near the throttle pedal or on the transmission itself.
Q: What happens if I ignore the P278C code?
A: Ignoring this code can lead to poor acceleration and potential transmission damage.
Q: Can I drive my car with the P278C code?
A: It is possible to drive, but it's recommended to have the issue diagnosed and repaired to prevent further problems.
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