Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer that controls the transmission has detected a problem with its memory, which helps it remember how to shift gears properly.
The Transmission Control Module (TCM) has a ROM that stores important data for the transmission's operation. A watchdog monitors this ROM for errors. If a problem is detected, this code is triggered.
The P17AF code indicates that the internal watchdog of the Transmission Control Module (TCM) has detected an error in the Read Only Memory (ROM). This ROM contains essential programming and data for the TCM to function correctly. An error in the ROM can lead to improper transmission operation.
• Check Engine Light is on
• Transmission may not shift properly
• Vehicle may enter 'limp mode' to prevent damage
• Faulty Transmission Control Module (TCM)
• Corrupted ROM data
• Electrical issues such as poor connections or damaged wiring
TCM: Transmission Control Module
ROM: Read Only Memory
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the P17AF code.
• Inspect the TCM and its connections for damage or corrosion.
• Check for any software updates or reprogramming needs for the TCM.
• Replace or reprogram the Transmission Control Module (TCM).
• Repair or replace any damaged wiring or connectors.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Screwdrivers and socket set
$300 - $1,200
Difficult
• Nissan Altima
• Infiniti Q50
• Nissan Maxima
• Regularly update vehicle software at the dealership.
• Ensure all electrical connections are clean and secure.
• Avoid driving through deep water that may damage electrical components.
Transmission Control Module Issue
• Have the vehicle checked by a professional mechanic.
• Avoid driving at high speeds until the issue is resolved.
• Keep a record of any repairs or updates done to the vehicle.
Check with the vehicle manufacturer for any applicable warranties on the TCM.
This code has been associated with vehicles using advanced electronic transmission controls, particularly in models with CVTs.
High – This issue can lead to transmission failure if not addressed promptly.
Driving with a faulty transmission can be dangerous. Address the issue as soon as possible to ensure vehicle safety.
• Vehicle should be at operating temperature.
• Transmission should be in normal operating mode.
The Transmission Control Module is typically located near the transmission or in the engine bay.
Q: Can I drive with a P17AF code?
A: It's not recommended to drive with this code as it can lead to further transmission damage.
Q: How do I reset the TCM?
A: Resetting the TCM usually requires a professional scan tool and should be done by a qualified mechanic.
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