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 noticed something unusual when the car was trying to change gears from the fourth gear to the second gear.
The transmission control module (TCM) is detecting an unexpected gear ratio when shifting from fourth to second gear.
P17F9 indicates that the TCM has detected a discrepancy between the expected and actual gear ratios during a shift from fourth to second gear. This could be due to slippage or other mechanical issues within the transmission.
• Harsh or delayed shifting
• Transmission slipping
• Check Engine Light illuminated
• Faulty transmission solenoid
• Worn clutch or bands
• Low transmission fluid level
Transmission Control Module (TCM): A computer that controls the transmission's operation.
Solenoid: An electromechanical device used to control fluid flow in the transmission.
• Check transmission fluid level and condition
• Scan for additional transmission-related codes
• Perform a transmission pressure test
• Replace faulty transmission solenoid
• Rebuild or replace worn clutches or bands
• Refill or replace transmission fluid
• OBD-II scanner
• Transmission pressure gauge
• Basic hand tools
$300 - $1500
Moderate
• Nissan Altima
• Infiniti Q50
• Nissan Maxima
• Regular transmission fluid changes
• Avoid aggressive driving
• Routine vehicle maintenance checks
Transmission Performance
• Avoid driving the vehicle aggressively until repaired
• Get the vehicle inspected by a professional
• Monitor for any worsening symptoms
Transmission repairs may be covered under powertrain warranty if the vehicle is within the warranty period.
This code has been associated with certain Nissan and Infiniti models, particularly those with CVT transmissions.
Moderate – Addressing this issue promptly can prevent further transmission damage.
Driving with transmission issues can lead to unsafe driving conditions and should be addressed as soon as possible.
• Vehicle at operating temperature
• Driving under normal conditions
The transmission is located beneath the vehicle, typically between the engine and the drive wheels.
Q: Can I drive my car with a P17F9 code?
A: It's not recommended to drive for extended periods with this code, as it may cause further damage to the transmission.
Q: How do I reset the P17F9 code?
A: After repairs, the code can be reset using an OBD-II scanner. However, it's important to fix the underlying issue first.
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