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 the car's computer has detected a problem with how the transmission shifts between the second and first gears.
The transmission control module (TCM) monitors the gear ratios during shifts. If the expected ratio isn't achieved during a shift from second to first gear, this code is set.
The P17EF code is triggered when the TCM detects an incorrect gear ratio during the transition from the second to the first gear. This could be due to a mechanical issue within the transmission or a problem with the transmission control system.
• Harsh shifting between gears
• Transmission slipping
• Check engine light illuminated
• Faulty transmission solenoid
• Worn or damaged transmission gears
• Low transmission fluid level
Transmission Control Module (TCM): A computer that controls the operation of the transmission.
Solenoid: An electromechanical device used to control the flow of transmission fluid.
• Check the transmission fluid level and condition.
• Inspect the transmission solenoids for proper operation.
• Perform a road test to observe the shifting behavior.
• Replace or repair the faulty transmission solenoid.
• Rebuild or replace the transmission if mechanical damage is found.
• Refill or replace the transmission fluid if necessary.
• OBD-II scanner
• Transmission fluid pressure gauge
• Basic hand tools
$500 - $2500
Moderate
• Nissan Altima
• Honda Accord
• Toyota Camry
• Regularly check and maintain transmission fluid levels.
• Service the transmission according to the manufacturer's schedule.
• Avoid aggressive driving that can stress the transmission.
Transmission Issue
• Have the vehicle inspected by a professional if you notice hard shifting.
• Avoid driving the vehicle until it is repaired to prevent further damage.
Check with your vehicle manufacturer for transmission warranty coverage.
This code has been associated with transmission issues in vehicles with higher mileage or poor maintenance history.
High – Addressing this issue promptly can prevent more serious transmission damage.
Driving with a transmission issue can lead to safety hazards and further vehicle damage.
• Vehicle at operating temperature
• Driving conditions that allow for shifting between second and first gear
The transmission is located between the engine and the drive wheels, usually beneath the vehicle.
Q: Can I drive with a P17EF code?
A: It's not recommended, as driving with this code can cause further transmission damage.
Q: How do I clear a P17EF code?
A: The code can be cleared with an OBD-II scanner, but it will return if the underlying issue is not fixed.
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