Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means the car's computer noticed a problem when shifting out of 5th gear. It's like when you try to switch gears on your bike, but the chain gets stuck.
The vehicle's transmission control module (TCM) detected an issue with the gear ratio when shifting from 5th gear. This could indicate a problem with the transmission's ability to shift gears smoothly.
The P18D5 code is triggered when the TCM identifies a discrepancy between the expected and actual gear ratio during a shift from 5th gear. This can be caused by mechanical issues within the transmission or problems with the sensors that monitor gear shifts.
• Check Engine Light is on
• Transmission slipping
• Difficulty shifting gears
• Faulty transmission solenoid
• Worn or damaged gear teeth
• Malfunctioning transmission control module
Transmission Control Module: A computer that controls the transmission's functions.
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 transmission fluid level and condition.
• Check for any visible damage to the transmission components.
• Replace faulty transmission solenoid.
• Repair or replace damaged gear teeth.
• Reprogram or replace the transmission control module.
• OBD-II scanner
• Transmission fluid dipstick
• Wrench set
$300 - $1500
Moderate
• Chevrolet Malibu
• Buick Regal
• Cadillac ATS
• Regular transmission fluid changes
• Routine transmission maintenance
• Avoid aggressive driving
Transmission Issue
• Avoid driving at high speeds until repaired.
• Consult with a certified mechanic for diagnosis.
• Monitor for any new symptoms or changes in vehicle performance.
Transmission issues may be covered under the powertrain warranty, typically lasting 5 years or 60,000 miles.
This code is relatively common in vehicles with high mileage or those that have not had regular transmission maintenance.
Moderate – It is advisable to address this issue soon to prevent further transmission damage.
Ignoring transmission issues can lead to unsafe driving conditions and potential vehicle breakdown.
• Vehicle must be driven to replicate the issue.
• Ensure the transmission fluid is at the correct level.
The transmission is located underneath the vehicle, connected to the engine.
Q: Can I drive with a P18D5 code?
A: It's not recommended to drive for extended periods with this code, as it can lead to further damage.
Q: Will fixing this code be expensive?
A: The cost can vary depending on the exact cause, ranging from a few hundred to over a thousand dollars.
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