AutoCodes – Chevrolet – P0721 2014 Chevrolet Silverado

P0721 2014 Chevrolet Silverado Code - Transmission Output Speed Sensor Performance

Quick Answer

The Output Speed Sensor (OSS) is a hall-effect type sensor. Common causes include Faulty Transmission Output Speed Sensor (OSS), Transmission Output Speed Sensor harness is open or shorted, Transmission Output Speed Sensor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P0721 2014 Chevrolet Silverado indicates Transmission Output Speed Sensor Performance.
Common causes: Common causes include Faulty Transmission Output Speed Sensor (OSS), Transmission Output Speed Sensor harness is open or shorted, Transmission Output Speed Sensor circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 357

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jul 29, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P0721 2014 Chevrolet Silverado Description

The Output Speed Sensor (OSS) is a hall-effect type sensor. The OSS mounts to the automatic transmission case assembly and connects to the control solenoid valve assembly through a 2-wire harness and connector. The sensor faces the park gear teeth. The sensor receives battery voltage on the OSS supply voltage circuit from the Transmission Control Module (TCM). As the output shaft rotates, the sensor produces a signal frequency based on the park gear teeth. This signal is transmitted through the OSS signal circuit to the TCM. The TCM uses the OSS signal to determine line pressure, transmission shift patterns, vehicle speed, and gear ratio.
The Diagnostic Trouble Code (DTC) will be set when the TCM detects a noisy output speed signal.

OBDII Code P0721 2014 Chevrolet Silverado - Transmission Output Speed Sensor Performance - AutoCodes.com — P0721 2014 Chevrolet Silverado Code - Transmission Output Speed Sensor Performance

What does this mean?

What are the Possible Causes of the DTC P0721 2014 Chevrolet Silverado?

Faulty Transmission Output Speed Sensor (OSS)
Transmission Output Speed Sensor harness is open or shorted
Transmission Output Speed Sensor circuit poor electrical connection
Faulty Transmission Control Module (TCM)

How to Fix the DTC P0721 2014 Chevrolet Silverado?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0721 2014 Chevrolet Silverado code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P0721 2014 Chevrolet Silverado code?

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0721 2014 Chevrolet Silverado Code

1. What does OBDII code P0721 mean for a 2014 Chevrolet Silverado?

Code P0721 indicates a problem with the transmission output speed sensor performance, which affects the vehicle's ability to accurately measure the transmission's output speed.

2. What are the common symptoms of P0721 in a 2014 Chevrolet Silverado?

Symptoms include erratic shifting, failure to shift gears, poor acceleration, a speedometer that doesnâ€™t work correctly, and the Check Engine Light turning on.

3. What causes the P0721 code on a 2014 Chevrolet Silverado?

The code can be triggered by a faulty transmission output speed sensor, damaged wiring or connectors, transmission fluid issues, or internal transmission problems.

4. How do you diagnose P0721 on a 2014 Chevrolet Silverado?

Diagnosis involves scanning for error codes, visually inspecting the wiring and connectors, testing the output speed sensor with a multimeter, and checking the transmission fluid level and condition.

5. Can driving with code P0721 damage my 2014 Chevrolet Silverado?

Yes, driving with this code can lead to further transmission issues due to incorrect gear shifting or prolonged poor performance.

6. How is the P0721 code fixed on a 2014 Chevrolet Silverado?

Repairs may include replacing the transmission output speed sensor, repairing damaged wiring, cleaning connectors, or addressing any internal transmission issues.

7. How much does it cost to fix the P0721 code on a 2014 Chevrolet Silverado?

Repair costs vary but typically range from $150 to $350 for parts and labor, depending on whether the sensor or wiring needs replacement.

8. Can low transmission fluid cause the P0721 code on a 2014 Chevrolet Silverado?

Yes, low or contaminated transmission fluid can cause issues with the sensorâ€™s performance and lead to this code.

9. Where is the transmission output speed sensor located on a 2014 Chevrolet Silverado?

The sensor is typically located on the transmission housing, near the output shaft or drive shaft.

10. Does the P0721 code require a professional mechanic to fix?

While some skilled DIYers can replace the sensor or repair wiring, itâ€™s recommended to consult a professional mechanic to ensure proper diagnosis and repair.