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 a part in the car that helps change gears is not working right. It's like when you try to switch TV channels, but the remote is not responding well.
The P0787 code indicates that the transmission control module (TCM) has detected a low voltage or signal from shift timing solenoid A, which is responsible for controlling the timing of gear shifts.
Shift solenoid A is part of the automatic transmission system that controls the flow of hydraulic fluid to change gears. A low signal can mean that the solenoid is not receiving enough power or is malfunctioning, affecting the timing of gear shifts.
• Erratic or harsh shifting
• Transmission slipping
• Check Engine Light is on
• Faulty shift solenoid A
• Wiring issues or poor electrical connections
• Transmission fluid level is low or contaminated
Solenoid: An electromagnetically operated valve.
Transmission: A system in a vehicle that transmits power from the engine to the wheels.
• Use an OBD-II scanner to confirm the code.
• Inspect the transmission fluid level and quality.
• Check the wiring and connectors to the shift solenoid.
• Replace the faulty shift solenoid A.
• Repair or replace damaged wiring or connectors.
• Change or refill the transmission fluid.
• OBD-II scanner
• Multimeter
• Transmission fluid level gauge
$150 - $400
Moderate
• Honda Accord
• Toyota Camry
• Ford F-150
• Regularly check and maintain transmission fluid levels.
• Perform routine transmission services.
• Inspect wiring and connectors for wear.
Transmission Control System Issue
• Avoid harsh driving until the issue is resolved.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle's warranty to see if transmission repairs are covered.
This code has been commonly associated with automatic transmission vehicles and is often due to electrical issues or solenoid failures.
Moderate – While the vehicle may still be drivable, it can lead to further transmission damage if not addressed.
Driving with a faulty transmission can be unsafe and may lead to damage over time. It's important to address this issue promptly.
• Engine at operating temperature
• Vehicle in drive mode
Shift solenoid A is located inside the transmission, usually accessible by removing the transmission pan.
Q: Can I drive with a P0787 code?
A: It is possible to drive, but it is not recommended as it may cause further damage to the transmission.
Q: How do I reset the P0787 code?
A: After repairs, use an OBD-II scanner to clear the code, but ensure the issue is fixed to prevent it from returning.
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