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 a part in the car that helps it change gears. It's like when a robot is supposed to move its arm, but it moves too fast or too much.
The transmission control module (TCM) has detected that the shift timing solenoid 'A' is operating at a higher voltage than expected.
The P0788 code is triggered when the TCM detects an abnormal high voltage condition in the shift timing solenoid 'A' circuit. This solenoid is responsible for controlling the timing of gear shifts in the transmission by regulating hydraulic pressure.
• Harsh or delayed shifting
• Transmission slipping
• Check Engine Light illuminated
• Faulty shift timing solenoid 'A'
• Wiring issues such as shorts or open circuits
• Faulty transmission control module (TCM)
TCM: Transmission Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Scan the vehicle for additional codes.
• Inspect the wiring and connectors to the shift timing solenoid.
• Test the shift timing solenoid for proper operation.
• Replace or repair faulty wiring or connectors.
• Replace the shift timing solenoid 'A'.
• Reprogram or replace the TCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Honda Accord
• Toyota Camry
• Ford F-150
• Regular transmission fluid changes
• Routine inspection of transmission components
• Avoiding aggressive driving habits
Transmission Issue
• Have the vehicle inspected by a professional mechanic.
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
Check with the vehicle manufacturer for warranty coverage on transmission components.
This code has been reported in vehicles with higher mileage or poor maintenance history.
Moderate – It should be addressed soon to avoid potential transmission damage.
Ignoring this code may lead to transmission failure, which can be dangerous while driving.
• Vehicle at operating temperature
• Vehicle in gear
The shift timing solenoid is located inside the transmission, usually accessible by removing the transmission pan.
Q: Can I drive with a P0788 code?
A: It's not recommended, as it can lead to further transmission damage.
Q: How do I reset the P0788 code?
A: After repairs, use an OBD-II scanner to clear the code.
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