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 shifting from 5th gear to 3rd gear. It's like when you try to change gears on a bicycle and it doesn't feel right.
The transmission control module (TCM) is detecting an issue with the gear ratio when shifting from 5th to 3rd gear.
The P17F8 code is triggered when the TCM detects that the actual gear ratio does not match the expected ratio during a shift from 5th to 3rd gear. This discrepancy can be due to mechanical or electronic issues within the transmission.
• Harsh or delayed shifting
• Transmission slipping
• Check Engine Light illuminated
• Faulty transmission solenoid
• Worn or damaged transmission gears
• Low transmission fluid level
Transmission: A system in a vehicle that transmits power from the engine to the wheels.
Solenoid: An electromechanical device used to control the flow of fluid in the transmission.
• Check transmission fluid level and condition.
• Perform a test drive to verify the issue.
• Use a scan tool to monitor transmission data.
• Replace faulty transmission solenoid.
• Repair or replace damaged gears.
• Refill or replace transmission fluid.
• OBD-II scan tool
• Transmission fluid dipstick
• Basic hand tools
$200 - $1500
Moderate
• Nissan Altima
• Nissan Maxima
• Infiniti Q50
• Regular transmission fluid changes
• Avoid aggressive driving
• Routine transmission inspections
Transmission Performance Issue
• Avoid driving at high speeds until repaired.
• Seek professional diagnosis promptly.
Transmission issues may be covered under powertrain warranty.
This code is often associated with Nissan's CVT transmission issues.
Moderate – Address soon to prevent further transmission damage.
Ignoring transmission issues can lead to unsafe driving conditions.
• Vehicle must be driven to replicate the shift.
• Transmission fluid at operating temperature.
The transmission is located between the engine and the drive wheels.
Q: Can I drive with a P17F8 code?
A: It's not recommended as it can cause further damage to the transmission.
Q: How do I reset the P17F8 code?
A: Fix the underlying issue and then use an OBD-II scanner to clear the code.
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