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 helps the car go faster when you press the gas pedal hard.
The P278B code indicates an issue with the kick down switch circuit, which is responsible for signaling the transmission to downshift for better acceleration.
The kick down switch is an electrical component that signals the transmission control module (TCM) to downshift the transmission when the accelerator pedal is pressed beyond a certain point. This allows for increased engine power and acceleration. A range/performance issue suggests that the switch is not operating within its expected parameters, which could be due to electrical faults or mechanical failure.
• Reduced acceleration
• Transmission not downshifting properly
• Check Engine Light illuminated
• Faulty kick down switch
• Wiring issues in the kick down switch circuit
• Malfunctioning transmission control module (TCM)
Kick Down Switch: A switch that signals the transmission to downshift for better acceleration.
Transmission Control Module (TCM): An electronic device that manages the operation of the transmission.
• Inspect the kick down switch and its wiring for damage.
• Test the switch for proper operation using a multimeter.
• Check the TCM for any related faults or errors.
• Replace the faulty kick down switch.
• Repair or replace damaged wiring in the circuit.
• Reprogram or replace the TCM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $300
Moderate
• Toyota Camry
• Honda Accord
• Ford Fusion
• Regularly inspect transmission components.
• Ensure electrical connections are secure.
• Perform routine vehicle maintenance.
Sensor Issue
• Avoid aggressive driving until the issue is resolved.
• Have the vehicle inspected by a professional mechanic.
Check with your vehicle manufacturer for specific warranty coverage related to transmission components.
This code has been associated with vehicles that have electronic transmission control systems, commonly reported in models with high mileage.
Moderate – While the vehicle may still be drivable, reduced performance and potential transmission damage make prompt attention advisable.
Driving with a malfunctioning transmission can be unsafe and may lead to further damage. 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 into the throttle assembly.
Q: Can I drive with a P278B code?
A: While the vehicle may still be drivable, it is not recommended due to reduced performance and potential for further damage.
Q: How is the kick down switch tested?
A: A multimeter can be used to test the switch's electrical continuity and function.
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