AutoCodes – Mercury – P0720 Mercury

P0720 Mercury Code - Output Shaft Speed Sensor Circuit Malfunction

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: P0720 Mercury indicates Output Shaft Speed Sensor Circuit Malfunction.
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.

Save to My Repairs Step-by-Step Diagnostic Guide My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 1,762

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
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P0720 Mercury 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 circuit malfunction.

OBDII Code P0720 Mercury - Output Shaft Speed Sensor Circuit Malfunction - AutoCodes.com — P0720 Mercury Code - Output Shaft Speed Sensor Circuit Malfunction

What does this mean?

What are the Possible Causes of the DTC P0720 Mercury?

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 P0720 Mercury?

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 P0720 Mercury 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 P0720 Mercury code?

Need more information on how to fix the P0720 Mercury code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0720 Mercury code diagnosed by a professional: Find a repair shop in your area

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 P0720 Mercury Code

1. What are the common symptoms of OBDII code P0720 on a Mercury vehicle?

The common symptoms of OBDII code P0720 on a Mercury include erratic speedometer readings, harsh shifting of the transmission, and the transmission going into limp mode.

2. What could cause the Output Shaft Speed Sensor Circuit Malfunction in a Mercury?

Possible causes of the P0720 code on a Mercury can include a faulty output shaft speed sensor, damaged wiring or connectors in the circuit, or issues with the transmission control module.

3. How can I diagnose the Output Shaft Speed Sensor Circuit Malfunction in my Mercury?

Diagnosing the P0720 code involves using a scan tool to read the code, checking the output shaft speed sensor and its wiring for any visible damage, and testing the sensor's resistance and output signal.

4. Can a bad output shaft speed sensor cause other problems in my Mercury?

Yes, a faulty output shaft speed sensor can cause issues such as incorrect gear shifting, reduced fuel efficiency, and potential damage to the transmission if left unresolved.

5. What are some repair tips for fixing the Output Shaft Speed Sensor Circuit Malfunction on a Mercury?

Repair tips for addressing the P0720 code can include replacing the faulty output shaft speed sensor, repairing any damaged wiring or connectors, and clearing the error code with a scan tool.

6. Is it safe to continue driving my Mercury with the P0720 code present?

It is not recommended to continue driving your Mercury with the P0720 code active, as it can lead to transmission issues and potential safety hazards. It's best to address the problem promptly.

7. How much does it typically cost to repair the Output Shaft Speed Sensor Circuit Malfunction on a Mercury?

The cost of repairing the P0720 code on a Mercury can vary depending on the extent of the issue and whether you do the repairs yourself or take it to a mechanic. Costs typically range from $100 to $300.

8. Can I reset the P0720 code on my Mercury without fixing the issue?

While you can clear the P0720 code using a scan tool, it is not advisable to do so without addressing the underlying problem, as it may lead to further damage and continued transmission issues.

9. Will disconnecting the battery reset the P0720 code on my Mercury?

Disconnecting the battery may temporarily clear the P0720 code, but it is not a recommended method for resolving the issue. The code is likely to return once the problem persists.

10. How long does it take to repair the Output Shaft Speed Sensor Circuit Malfunction on a Mercury?

The repair time for the P0720 code can vary depending on the complexity of the issue and your level of experience. A professional mechanic may take around 1-2 hours to diagnose and fix the problem.