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 car's switch that lets you choose between normal driving and performance mode. It's like when a video game controller button doesn't work right.
The P0790 code indicates an issue with the circuit that controls the switch between normal and performance driving modes in a vehicle.
The P0790 code is triggered when the transmission control module (TCM) detects a malfunction in the circuit responsible for the normal/performance switch. This switch allows the driver to select between different driving modes, which can affect the vehicle's performance and fuel efficiency.
• Inability to switch between driving modes
• Check Engine Light illuminated
• Possible transmission performance issues
• Faulty normal/performance switch
• Damaged wiring or connectors in the switch circuit
• Malfunctioning transmission control module (TCM)
TCM: Transmission Control Module
OBD-II: On-Board Diagnostics II
• Check for any other related trouble codes.
• Inspect the normal/performance switch for damage.
• Examine the wiring and connectors for any signs of wear or damage.
• Replace the normal/performance switch if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the TCM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $500
Moderate
• Toyota Camry
• Honda Accord
• Ford Fusion
• Regularly inspect and maintain the vehicle's electrical system.
• Avoid using excessive force on the driving mode switch.
• Keep the vehicle's software updated.
Transmission Control System Issue
• Avoid aggressive driving until the issue is resolved.
• Consult a professional mechanic for a thorough diagnosis.
Check with your vehicle manufacturer for warranty coverage on transmission components.
The P0790 code has been more prevalent in vehicles with advanced transmission systems that offer multiple driving modes.
Moderate – While the vehicle may still be drivable, it is recommended to address the issue to ensure optimal performance.
Driving with a malfunctioning transmission system can lead to reduced vehicle performance and may affect safety.
• Vehicle must be in a safe, stationary position.
• Ensure the engine is off before inspecting electrical components.
The normal/performance switch is typically located on the vehicle's dashboard or center console.
Q: Can I drive my car with a P0790 code?
A: Yes, but it's best to get it checked soon to avoid potential transmission issues.
Q: How do I reset the P0790 code?
A: After repairs, use an OBD-II scanner to clear the code from the vehicle's computer.
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