U0155 code — how to fix error fast

The code U0155 is one of those OBD2 error codes that may look harmless at first but can cause quite a stir in your vehicle’s instrument cluster system. The code is one of those codes that could consequently lead to issues with your car’s powertrain performance, which is why it’s so important to understand the U0155 code meaning.

Our team wanted to share some of our first-hand experience with the code and give you an overview of how it can affect your car based on the expertise of our automotive enthusiasts. So, sit tight as we go through the meaning of the code, ways of diagnosing and fixing it, and the most common reasons behind the code.

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What does the U0155 code mean?

The U0155 code is a generic powertrain code. It means that the communication between the PCM (powertrain control module) and the instrument cluster has been lost. When the PCM and the instrument cluster cannot communicate, the check engine light will turn on, and the driver may experience other issues, such as a loss of power or malfunctioning gauges.

It’s important to note that the U0155 code is not specific to any particular make or model of vehicle. If you receive this code, it’s essential to diagnose and fix the issue as soon as possible.

What causes the U0155 code?

The consequences of code U0155 can be pretty dire if your speedometer starts providing inaccurate readings or if the gauges of your car start rapidly malfunctioning. It gets difficult to keep track of your car’s performance, fuel level, and boost if the code tampers with the key systems, so here are some of the main reasons behind it:

Faulty connections

One of the most common causes of the U0155 code is a faulty or loose connection. This can happen due to corrosion or damage to the wiring harness or connectors. When this occurs, the PCM and the instrument cluster cannot communicate, leading to the U0155 code.

Malfunctioning instrument cluster

If the instrument cluster is malfunctioning, it can cause a failure in communication with the PCM. This can happen due to a faulty circuit board or a loose connection.

Defective PCM

In some cases, the PCM itself may be faulty, leading to the U0155 code. This is a less common cause but can happen if the PCM has failed or has been damaged.

Which car models does the U0155 code affect the most?

The U0155 code can affect any make or model of vehicle, but some cars are more prone to this issue. We decided to do some more digging to figure out how to deal with this code, which is why we decided to list a few vehicles with the highest tendency of being prone to the code for various reasons:

• Ford Focus: The Ford Focus is a popular compact car that has been known to experience U0155 codes due to issues with its body control module or powertrain control module.
• Dodge RAM: The Dodge Ram is a full-size pickup truck that may encounter U0155 codes due to problems with its powertrain control module or communication network module.
• Chevrolet Cruze: The Chevrolet Cruze is another compact car that may be susceptible to U0155 codes, especially in the 2011-2016 models. This code can be caused by a faulty electronic brake control module or a bad connection in the wiring harness.

How to diagnose the U0155 code

Diagnosing the U0155 code requires a diagnostic scanner, which can read the code and determine the issue. Here are the steps to diagnose the code:

Check for other codes

Before diagnosing the U0155 code, it’s essential to check for any other codes that may be present. This can help determine if there are any other issues that need to be addressed.

Inspect wiring harness and connectors

Inspect the wiring harness and connectors for any damage or corrosion. If there are no visible issues, use a multimeter to test the connections for continuity.

Check the instrument cluster

Check the instrument cluster for any issues, such as a faulty circuit board or loose connections.

Check the PCM

If the wiring harness, connectors, and instrument cluster are all in good condition, the issue may be with the PCM. Use a diagnostic scanner to check the PCM for any faults or issues.

How to fix the U0155 code

Once you’ve finally got a sense of what may be causing the code U0155 in your car, it’s time to get to the crucial point – finding a solution for it. Our team has encountered numerous different fixing methods, and these are some of the options we can recommend as the most effective based on the underlying problem:

Reset the vehicle’s modules

Sometimes, simply resetting the vehicle’s modules can clear the U0155 code. This can be done by disconnecting the battery for a few minutes, or by using a scan tool to reset the codes.

Replace or reprogram faulty modules

If a specific module is found to be faulty, it may need to be replaced. This can involve locating and removing the faulty module, then installing a new one.

Update the software

In some cases, software updates may be available for the vehicle’s modules. These updates can address known issues that can cause the U0155 code to appear.

How to prevent the U0155 code

Preventing the U0155 code requires proper maintenance and care for your vehicle. Here are some tips to prevent the U0155 code from appearing:

• Regularly inspect and clean connectors and wiring harnesses
• Perform routine maintenance on the instrument cluster
• Avoid using aftermarket parts that may cause issues with communication between the PCM and instrument cluster

So, regular maintenance and care can help prevent the code from appearing, ensuring that your vehicle runs smoothly even with the simplest form of preventive action taken.

Our take

The code U0155 is pretty bad on its own, but you may get the worst out of it in case something is wrong with your vehicle and the code interferes with the diagnostic system and the gauges of your dashboard. If you don’t get what’s causing the trouble, you won’t be able to fix it, and the code U0155 surely makes it harder as it can cut the power of the warning lights.

So, we hope this guide was helpful enough to give you a way out of such a situation and enable you to preserve your vehicle’s mechanical systems.