P0720 code — how to fix error fast

When it comes to car maintenance, understanding error codes like the P0720 code is crucial. If this code appears, you’ll want to know everything about the P0720 code meaning, how you can figure out the root cause of it, and eventually fix it.

So, this article will cover everything you need to know about the P0720 code, including its meaning, potential causes, diagnostic steps, and solutions. We’ll also include a few preventive measures so you can avoid allowing the code to show up on the scanner tool in the first place this time around.

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What does the P0720 code mean?

The P0720 code is a diagnostic trouble code that indicates an issue with the vehicle’s output speed sensor circuit. This sensor is responsible for monitoring the speed of the output shaft of the transmission. The code is often found in vehicles with an automatic transmission.

The importance of understanding this code lies in the fact that it can cause serious performance issues and even lead to transmission failure if left untreated. We don’t have to say that twice for you to figure out it can even compromise your driving safety if you choose not to fix the issue immediately.

What causes the P0720 code?

The code P0720 can be caused by several different problems in your car, and some of the main symptoms that may be present with the P0720 code include a malfunctioning speedometer, difficulty shifting gears, and the transmission staying in limp mode.

So, it’s all up to your ability to pinpoint the exact cause so you can promptly fix the damage, and here’s our list of the most common culprits behind the code:

Bad output speed sensor

The output speed sensor may be damaged or not functioning correctly, leading to an inaccurate reading of the transmission’s output speed. If this happens, transmission problems become inevitable unless you replace the sensor, and the good thing is you can test it yourself by using a multimeter.

Damaged wiring or connections

The wiring that connects the output speed sensor to the engine control module may be damaged or corroded, leading to a lack of communication between the two components.

Faulty ECU

The engine control unit may be malfunctioning, preventing it from receiving accurate data from the output speed sensor. If this happens, the report on the transmission output speed issue may not be accurate, but you’ll just have another huge issue at hand since replacing the ECU can be rather expensive.

Which car models does the P0720 code affect the most?

While any car can potentially experience code P0720, there are certain models that have been known to be more prone to this issue. Our team did some digging, so here’s what we’ve found out:

• Honda Civic: The Civic is one of the most popular compact cars on the market, but it has been known to experience issues with the output shaft speed sensor circuit that can trigger code P0720.
• Dodge RAM: The Ram is a popular pickup truck that has also been known to experience this issue. In some cases, the transmission control module on the Ram may need to be reprogrammed to resolve this problem.
• Nissan Altima: The Altima is a midsize sedan that has been known to experience issues with the output shaft speed sensor circuit. In some cases, the sensor may need to be replaced to fix the problem.
• Jeep Grand Cherokee: The Grand Cherokee is a midsize SUV that has also been known to experience this issue. In some cases, the wiring harness for the output shaft speed sensor may need to be repaired or replaced.

How to diagnose the P0720 code

To diagnose the P0720 code properly, you’ll need a set of diagnostic tools including a scanner tool, a multimeter, and a wiring diagram. The thing is – most drivers aren’t that familiar with using all these tools to test the code and sensor’s resistance, so here are some other ways you can test the code and leave the hard part to your mechanic:

Check the output shaft speed sensor

The output shaft speed sensor is a critical component of the transmission system that provides data to the vehicle’s computer. Inspecting the sensor for damage or wear can help identify any issues that may be contributing to code P0720.

Test the wiring and connections

Faulty wiring or connectors can cause issues with the output shaft speed sensor circuit. Testing these components for continuity, resistance, and voltage drop can help identify any problems.

Check the transmission fluid level and condition

Low transmission fluid levels or contaminated fluid can cause issues with the output shaft speed sensor circuit. Checking the fluid level and condition can help identify any problems and prevent future issues.

How to fix the P0720 code

Now that you know what may cause the issue and how to diagnose it, you’ll need to learn the common ways of dealing with the code. Fixing this code can involve several methods, depending on the underlying cause of the issue. Here are some of the main methods of fixing code P0720:

Replace the output shaft speed sensor

If the sensor is faulty or damaged, it may need to be replaced. This is often the most effective way to resolve code P0720.

Deal with faulty wiring or connections

Faulty wiring or connectors can cause issues with the output shaft speed sensor circuit. Repairing or replacing these components can help resolve code P0720.

Top up or replace your transmission fluid

Low or contaminated transmission fluid can cause issues with the output shaft speed sensor circuit. Checking and replacing the fluid can help prevent future issues.

Replace the transmission control module

In rare cases, a faulty transmission control module may be causing code P0720. In this case, replacing the module may be necessary to fix the problem.

How to prevent the P0720 code

Preventative measures can be taken to help prevent the P0720 code from appearing. Routine maintenance tasks such as the listed ones can greatly help you avoid dealing with this code ever again:

• Timely changing of the transmission fluid
• Checking the transmission fluid condition
• Inspecting the wiring related to the sensor
• Stick with the maintenance schedule proposed by the manufacturer

Taking these steps can eventually save you from having to do some more expensive repairs, and it will also have a positive effect on your car’s transmission as a whole.

Our take

In the end, facing the code P0720 isn’t as bad as it sounds as long as you know what to do to diagnose the issue and fix it. We hope that this guide will be just what you needed in that spite, so you can get straight to the fixing part and apply the preventive measures to avoid the code from re-appearing.