AutoCodes – Ford – P0721 1999 Ford F150

P0721 1999 Ford F150 Code - Output Shaft Speed Sensor Range/Performance

Quick Answer

The Output Shaft Speed (OSS) Sensor provides the Powertrain Control Module (PCM) with information about the rotational speed of an output shaft. Common causes include Faulty Output Speed Sensor (OSS), Output Speed Sensor harness is open or shorted, 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 1999 Ford F150 indicates Output Shaft Speed Sensor Range/Performance.
Common causes: Common causes include Faulty Output Speed Sensor (OSS), Output Speed Sensor harness is open or shorted, 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 2,275

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 13, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P0721 1999 Ford F150 Description

The Output Shaft Speed (OSS) Sensor provides the Powertrain Control Module (PCM) with information about the rotational speed of an output shaft. The PCM uses the information to control and diagnose powertrain behavior. In some applications, the sensor is also used as the source of vehicle speed. The sensor may be physically located in different places on the vehicle, depending upon the specific application. The design of each speed sensor is unique and depends on which powertrain control feature uses the information that is generated. The Diagnostic Trouble Code (DTC) will set if the PCM detects an OSS sensor out of range circuit.

OBDII Code P0721 1999 Ford F150 - Output Shaft Speed Sensor Range/Performance - AutoCodes.com — P0721 1999 Ford F150 Code - Output Shaft Speed Sensor Range/Performance

What does this mean?

What are the Possible Causes of the DTC P0721 1999 Ford F150?

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

How to Fix the DTC P0721 1999 Ford F150?

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 1999 Ford F150 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.

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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 1999 Ford F150 Code

1. What does OBDII code P0721 on a 1999 Ford F150 mean?

The code P0721 indicates an issue with the Output Shaft Speed Sensor, specifically relating to range/performance.

2. What are common symptoms of a P0721 code in a 1999 Ford F150?

Common symptoms include erratic shifting, harsh shifting, transmission slippage, and the transmission going into limp mode.

3. What are possible causes of a P0721 code in a 1999 Ford F150?

Potential causes include a faulty output shaft speed sensor, damaged wiring or connectors, low transmission fluid levels, or internal transmission issues.

4. How can I diagnose a P0721 code on my 1999 Ford F150?

Diagnosis involves checking the output shaft speed sensor for proper operation, inspecting the wiring and connectors for damage, and ensuring the transmission fluid levels are correct.

5. Can I continue driving my 1999 Ford F150 with a P0721 code?

It is not recommended to drive with a P0721 code as it can lead to further transmission damage and safety hazards. It's best to address the issue promptly.

6. How do I repair a P0721 code on my 1999 Ford F150?

Repairing a P0721 code typically involves replacing the output shaft speed sensor, repairing any damaged wiring or connectors, and ensuring the transmission fluid is at the correct level.

7. Is it possible to reset a P0721 code on a 1999 Ford F150 without fixing the issue?

Resetting the code without addressing the underlying problem will likely result in the code reappearing once the vehicle is driven and the issue is detected again.

8. Can a DIY enthusiast fix a P0721 code on a 1999 Ford F150?

Depending on their skill level and experience with automotive repairs, a DIY enthusiast may be able to replace the output shaft speed sensor and address wiring issues related to the P0721 code.

9. How much does it cost to repair a P0721 code on a 1999 Ford F150?

The cost of repairing a P0721 code can vary depending on the labor rates in your area, the cost of parts, and whether you choose to DIY or take it to a professional mechanic.

10. Will a P0721 code on a 1999 Ford F150 affect fuel efficiency?

A P0721 code can potentially affect fuel efficiency due to transmission issues causing the engine to work harder. Addressing the code promptly can help maintain optimal fuel efficiency.