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 a part in your car's transmission isn't communicating correctly with the car's computer. It's like when two friends can't understand each other because they're speaking different languages.
The vehicle's computer has detected that the data from the pressure control solenoid J is not compatible with the expected parameters.
P27AF is triggered when the transmission control module (TCM) identifies a mismatch or incompatibility in the data received from the pressure control solenoid J. This solenoid is responsible for regulating hydraulic pressure in the transmission, which is crucial for smooth gear shifts.
• Harsh or erratic shifting
• Transmission slipping
• Illuminated check engine light
• Faulty pressure control solenoid J
• Wiring issues or poor connections
• Faulty transmission control module (TCM)
Transmission Control Module (TCM): A computer that controls the operation of the transmission.
Solenoid: An electromechanical device used to control the flow of fluid in the transmission.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the pressure control solenoid J for proper operation.
• Replace or repair the pressure control solenoid J.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the transmission control module (TCM) if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular transmission fluid checks and changes.
• Routine inspections of wiring and connectors.
• Avoid aggressive driving to reduce transmission strain.
Transmission Control Issue
• Drive gently until the issue is resolved.
• Avoid long trips if possible.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle manufacturer for specific warranty coverage related to transmission issues.
This code has been associated with vehicles experiencing communication issues between the TCM and transmission components, often due to solenoid failures.
Moderate – While the vehicle may still be drivable, ignoring this issue can lead to more severe transmission problems.
Driving with transmission issues can be unsafe and may lead to further damage. Address this code promptly to ensure vehicle safety and compliance with emission standards.
• Vehicle at normal operating temperature
• Transmission in drive mode
The pressure control solenoid J is located within the transmission valve body, which is typically found under the vehicle or within the engine bay.
Q: Can I drive with a P27AF code?
A: It's possible, but not recommended. Driving with this code can lead to further transmission damage.
Q: How is the pressure control solenoid tested?
A: A multimeter is used to check the solenoid's resistance and functionality, and an OBD-II scanner can verify its performance.
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