• Check Engine Light is on
• Transmission may not shift properly
• Speedometer may not work correctly
• Faulty output shaft speed sensor
• Damaged wiring or connectors
• Faulty transmission control module (TCM)
TCM: Transmission Control Module
OBD-II: On-Board Diagnostics, second generation
• P0721
• P0722
Output Shaft Speed Sensor Circuit
This code means that the car's computer is having trouble reading the speed of a part that helps the car change gears properly.
The P0720 code is triggered when the transmission control module (TCM) detects a malfunction in the output shaft speed sensor circuit.
The output shaft speed sensor measures the rotational speed of the transmission's output shaft. This data is used by the TCM to control the shift points and ensure the transmission operates smoothly. If the sensor or its circuit fails, the TCM may not be able to determine the output shaft speed, resulting in improper shifting.
• Use an OBD-II scanner to confirm the P0720 code is present.
• Inspect the output shaft speed sensor and its wiring for damage.
• Test the sensor using a multimeter to ensure it is functioning correctly.
• Replace the output shaft speed sensor if it is faulty.
• Repair or replace damaged wiring or connectors.
• Replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$150 - $400
Moderate
• Ford F-150
• Honda Accord
• Toyota Camry
• Regularly inspect and maintain transmission components.
• Address any Check Engine Light warnings promptly.
• Ensure wiring and connectors are in good condition.
Sensor Issue
• Avoid driving at high speeds until the issue is resolved.
• Consult a professional mechanic if unsure about repairs.
Check with the vehicle manufacturer for specific warranty coverage on transmission components.
The P0720 code has been a common diagnostic trouble code for vehicles with automatic transmissions, especially as vehicles age.
Moderate – While the vehicle may still be drivable, improper shifting can lead to further transmission damage if not addressed.
Driving with a malfunctioning transmission can be dangerous. Ensure repairs are made promptly to maintain vehicle safety.
• Vehicle should be on a level surface.
• Ensure the engine is off and the key is removed before inspecting components.
The output shaft speed sensor is typically located on the transmission, near the output shaft.
Q: Can I drive with a P0720 code?
A: It's possible, but not recommended. Driving with this code can lead to further transmission damage.
Q: How do I reset the P0720 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, it should not return.
