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 switch that helps the car go faster when you press the gas pedal hard. It's like if a button on your video game controller wasn't working right.
The P278D code is triggered when the transmission control module (TCM) detects a high voltage condition in the kick down switch circuit.
The kick down switch is a component that signals the transmission to downshift when the accelerator pedal is pressed rapidly. A 'high' circuit condition indicates that the voltage in the circuit is higher than expected, which could be due to a wiring issue, a faulty switch, or a problem with the TCM.
• Poor acceleration
• Transmission not downshifting properly
• Check engine light illuminated
• Faulty kick down switch
• Wiring issues such as shorts or open circuits
• Malfunctioning transmission control module (TCM)
Kick Down Switch: A switch that signals the transmission to downshift when the accelerator is pressed rapidly.
Transmission Control Module (TCM): A computer that controls the operation of the vehicle's transmission.
• Scan the vehicle for additional codes
• Inspect the wiring and connectors related to the kick down switch
• Test the kick down switch for proper operation
• Repair or replace damaged wiring
• Replace the faulty kick down switch
• Reprogram or replace the TCM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Toyota Camry
• Honda Accord
• Ford Focus
• Regularly inspect wiring for damage
• Ensure connectors are secure
• Perform routine maintenance checks
Sensor Issue
• Avoid aggressive driving until the issue is resolved
• Schedule a diagnostic check with a professional mechanic
Check with the vehicle manufacturer for warranty coverage on transmission components.
This code has been more commonly reported in vehicles with higher mileage and those frequently used in stop-and-go traffic.
Moderate – While the vehicle may still be drivable, reduced performance and potential transmission damage make it important to address the issue promptly.
Driving with a malfunctioning transmission can lead to unsafe driving conditions. Address the issue as soon as possible to ensure vehicle safety.
• Engine running
• Vehicle in motion
The kick down switch is typically located near the accelerator pedal or integrated into the throttle assembly.
Q: Can I drive with a P278D code?
A: It's possible to drive with this code, but it is not recommended due to potential transmission issues and reduced performance.
Q: How do I reset the check engine light after fixing the issue?
A: After repairs, use an OBD-II scanner to clear the code and reset the check engine light.
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