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 sensor which tells how fast the wheels are turning is sending a signal that's too strong.
The Output Shaft Speed Sensor is responsible for providing data to the transmission control module (TCM) about the speed of the transmission's output shaft. A 'Circuit High' error indicates that the voltage from this sensor is above the expected range.
The P077D code is triggered when the powertrain control module (PCM) detects an abnormally high voltage signal from the output shaft speed sensor circuit. This sensor measures the rotational speed of the transmission's output shaft and sends this data to the TCM to help regulate transmission operation.
• Check Engine Light illuminated
• Erratic or harsh shifting
• Transmission slipping
• Faulty output shaft speed sensor
• Wiring issues such as short circuits or open circuits
• Faulty transmission control module (TCM)
PCM: Powertrain Control Module
TCM: Transmission Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the output shaft speed sensor for proper operation.
• Replace the output shaft speed sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the TCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and maintain vehicle wiring.
• Ensure connectors are clean and secure.
• Follow the manufacturer's maintenance schedule.
Sensor Issue
• Avoid driving at high speeds until the issue is resolved.
• Consult a professional mechanic if unsure about repairs.
Check if the vehicle's powertrain warranty covers sensor-related issues.
This code has been associated with sensor failures and wiring issues in various vehicle models over the years.
Moderate – While the vehicle may still be operable, ignoring the issue could lead to more severe transmission problems.
Driving with a malfunctioning speed sensor can lead to unsafe driving conditions and may affect vehicle performance.
• Vehicle at operating temperature
• Transmission in drive mode
The output shaft speed sensor is typically located on the transmission housing, near the output shaft.
Q: Can I drive with a P077D code?
A: It's not recommended, as it may cause transmission issues and unsafe driving conditions.
Q: How do I reset the P077D code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, it should not return.
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