Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is having trouble understanding if the brake pedal is being pressed or not.
The P0703 code indicates a problem with the electrical circuit of the brake switch, which is responsible for telling the car's computer when the brake pedal is pressed.
The Brake Switch B Circuit is part of the vehicle's brake light system and is used to inform the transmission control module (TCM) and engine control module (ECM) when the brake pedal is applied. This information is crucial for various functions, including cruise control and transmission shifting. A fault in this circuit can disrupt these systems.
• Brake lights not working
• Cruise control not functioning
• Transmission shift problems
• Faulty brake switch
• Damaged or corroded wiring or connectors
• Blown fuse related to the brake light circuit
Brake Switch: A device that signals the vehicle's computer when the brake pedal is pressed.
Circuit: A complete path for electrical current.
• Check the brake lights for proper operation.
• Inspect the brake switch and its wiring for damage or corrosion.
• Test the brake switch with a multimeter to ensure it is functioning correctly.
• Replace the faulty brake switch.
• Repair or replace damaged wiring or connectors.
• Replace any blown fuses related to the brake circuit.
• Multimeter
• Screwdriver set
• Wire stripper/crimper
$50 - $200
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check brake lights for proper operation.
• Inspect wiring for signs of wear or damage.
• Ensure the brake switch is adjusted correctly.
Sensor Issue
• Avoid using cruise control until the issue is resolved.
• Have the brake system inspected by a professional if unsure about repairs.
Brake switch issues may be covered under the vehicle's basic warranty if the vehicle is relatively new.
P0703 has been a common code in vehicles with older brake light systems, particularly those with mechanical switches prone to wear.
Moderate – While the vehicle can still be driven, brake light and cruise control functions may be impaired, which can affect safety.
Driving without functioning brake lights is illegal and unsafe. Ensure repairs are made promptly.
• Vehicle parked with engine off
• Access to brake pedal and switch
The brake switch is typically located near the top of the brake pedal arm under the dashboard.
Q: Can I drive with a P0703 code?
A: While you can drive, it's not recommended due to potential safety issues with brake lights and cruise control.
Q: How do I know if my brake switch is bad?
A: If your brake lights don't work or the cruise control is malfunctioning, the brake switch may be faulty.
Pro · Four-system diagnostics
A handheld scanner aimed at engine, transmission, ABS, and airbag diagnostic work.
Chassis and ABS faults usually need a scanner that can read brake-system data directly.
View on Amazon
Universal · Torque wrench
Useful when reassembly torque matters for wheel, suspension, and under-hood fasteners.
Useful when wheel, hub, or suspension hardware needs correct reassembly torque.
View on Amazon
Universal · Drive-on ramps
Helpful for safer access underneath the vehicle during exhaust, EVAP, and underbody inspection work.
Helpful for safer access during underbody inspection work.
View on AmazonThese are optional diagnostic tools, not guaranteed fixes. As an Amazon Associate I earn from qualifying purchases.