Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This means that when the car is trying to use the sixth gear, something isn't working right, like when a bike chain skips a gear.
The transmission control module (TCM) monitors the gear ratios of the transmission. If it detects that the actual gear ratio for the sixth gear is different from the expected ratio, it triggers the P0729 code.
The P0729 code indicates that the transmission control module has detected an incorrect gear ratio for the sixth gear. This can be caused by mechanical issues within the transmission, such as a slipping clutch, or by electronic issues, such as a faulty speed sensor.
• Check Engine Light is on
• Poor acceleration
• Transmission slipping or not shifting properly
• Faulty transmission solenoid
• Worn out clutch or transmission bands
• Defective speed sensor
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 for other transmission-related codes.
• Inspect the transmission fluid level and condition.
• Test the operation of the transmission solenoids and sensors.
• Replace faulty transmission solenoid.
• Repair or replace worn clutch components.
• Replace defective speed sensor.
• OBD-II scanner
• Multimeter
• Transmission fluid pressure gauge
$300 - $1500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular transmission fluid changes
• Avoid aggressive driving
• Routine transmission inspections
Transmission Issue
• Avoid driving at high speeds until repaired.
• Get the transmission inspected by a professional.
Transmission repairs may be covered under the powertrain warranty, typically 5 years or 60,000 miles.
P0729 is a relatively common code in vehicles with automatic transmissions, often related to wear and tear over time.
Moderate – While the vehicle may still be drivable, ignoring the issue can lead to more severe transmission damage.
Driving with a faulty transmission can be dangerous and may lead to further damage.
• Vehicle should be driven to simulate normal driving conditions.
• Transmission should be allowed to shift through all gears.
The transmission is located between the engine and the drive wheels, usually underneath the vehicle.
Q: Can I drive with a P0729 code?
A: It's not recommended as it can cause further damage to the transmission.
Q: How do I know if my transmission is slipping?
A: You may notice poor acceleration, a delay in shifting, or a high engine RPM without speed increase.
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