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 is saying that the gears aren't working right when you try to go backward.
The transmission control module (TCM) detects an incorrect gear ratio in the second reverse gear.
The P077F code is triggered when the TCM detects that the actual gear ratio in the second reverse gear does not match the expected ratio. This could be due to a mechanical failure in the transmission, a problem with the transmission fluid, or an issue with the transmission sensors.
• Check Engine Light is on
• Difficulty in shifting gears
• Vehicle may not move in reverse
• Low or dirty transmission fluid
• Faulty transmission solenoid
• Mechanical failure in the transmission
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
• Inspect transmission solenoids for proper operation
• Perform a transmission pressure test
• Replace or top up transmission fluid
• Replace faulty transmission solenoid
• Rebuild or replace the transmission if necessary
• OBD-II scanner
• Transmission fluid dipstick
• Basic hand tools
$300 - $2500
Difficult
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and change transmission fluid
• Avoid aggressive driving that strains the transmission
• Perform regular transmission maintenance
Transmission Issue
• Do not ignore the Check Engine Light
• Have the vehicle inspected by a professional
• Avoid driving the vehicle until repaired
Check with your vehicle manufacturer for specific warranty coverage on transmission components.
The P077F code has been associated with transmission issues in vehicles with automatic transmissions, especially as they age.
High – This issue can lead to transmission failure if not addressed promptly.
Driving with a malfunctioning transmission can be dangerous and may lead to further vehicle damage.
• Vehicle in reverse
• Transmission at operating temperature
The transmission is located between the engine and the driveshaft, underneath the vehicle.
Q: Can I drive with a P077F code?
A: It's not recommended to drive with this code active as it can lead to further damage.
Q: What happens if I ignore the P077F code?
A: Ignoring this code can result in severe transmission damage and costly repairs.
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