C1748 DTC Code: Understanding and Resolving the Issue


When it comes to automotive diagnostics, the C1748 DTC code is one that might leave vehicle owners scratching their heads. This diagnostic trouble code represents a specific issue that needs to be addressed. In this article, we will delve into what the C1748 DTC code means, its potential causes, and how to resolve the underlying problem. So, let’s dive in!

What is the C1748 DTC Code?

The C1748 DTC code stands for “Suspension Level Control Output Open Circuit.” This code is specific to vehicles equipped with a suspension level control or air suspension system. It indicates that there is an open circuit somewhere in the suspension control module or a related component.

Understanding the Causes

To effectively diagnose and resolve the C1748 DTC code, it’s crucial to understand the potential causes. Here are some common culprits:

1. Faulty Suspension Height Sensor

One possible cause of the C1748 DTC code is a faulty suspension height sensor. This sensor is responsible for measuring the vehicle’s ride height and relaying the information to the suspension control module. If the sensor malfunctions or fails, it can trigger the C1748 code.

2. Wiring or Connector Issues

Another frequent cause of the C1748 DTC code is wiring or connector problems. Over time, the wires can become worn, damaged, or disconnected, leading to an open circuit. Similarly, loose or corroded connectors can disrupt the flow of electrical signals, triggering the code.

3. Suspension Control Module Failure

A malfunctioning suspension control module can also trigger the C1748 DTC code. If the control module responsible for managing the air suspension system malfunctions or fails, it may generate an open circuit error, resulting in the code being stored in the vehicle’s onboard computer.

Resolving the C1748 DTC Code

Now that we have a better understanding of the C1748 DTC code and its potential causes, let’s explore the steps to resolve the issue effectively:

  1. Diagnostic Trouble Code Clearing: First and foremost, it is recommended to clear the DTC code using a professional automotive scan tool. This allows you to start with a clean slate before proceeding with further diagnostics.

  2. Inspecting and Testing Suspension Height Sensor: Carefully inspect the suspension height sensor for any visible damage or signs of wear. If necessary, consult the vehicle’s service manual for guidance on testing the sensor’s resistance and voltage output using a multimeter. Replace the sensor if it is found to be faulty.

  3. Checking Wiring and Connectors: Thoroughly inspect the wiring harness and connectors associated with the suspension control module. Look for any signs of damage, corrosion, or loose connections. Repair or replace the wiring and connectors as needed.

  4. Testing the Suspension Control Module: If the previous steps do not resolve the issue, consider testing the suspension control module itself. This may require specialized diagnostic equipment or the assistance of a professional mechanic. If the control module is diagnosed as faulty, it will need to be replaced.

Frequently Asked Questions

  1. Q: Can I continue driving my vehicle with the C1748 DTC code?

    • A: It is generally not recommended to drive your vehicle with an unresolved DTC code, as it indicates a potential problem with the suspension system. Continued driving without addressing the issue may result in further damage or safety concerns. It is best to have the problem diagnosed and resolved promptly.
  2. Q: How much does it cost to fix the C1748 DTC code?

    • A: The cost of fixing the C1748 DTC code can vary depending on the specific cause and the labor rates of the repair facility. Repair costs may involve replacing a faulty suspension height sensor, repairing wiring or connectors, or replacing the suspension control module. It is advisable to obtain quotes from reputable mechanics to get an accurate estimate.
  3. Q: Can I fix the C1748 DTC code myself, or do I need a professional mechanic?

    • A: While it is possible for experienced DIY enthusiasts with the appropriate tools and knowledge to address some of the potential causes of the C1748 DTC code, it is generally recommended to seek the assistance of a professional mechanic. They have the expertise and specialized equipment to accurately diagnose and resolve the issue, ensuring a proper repair.


The C1748 DTC code related to suspension level control output open circuit can be a cause of concern for vehicle owners. However, armed with a better understanding of the code and its potential causes, you can now take the necessary steps to diagnose and resolve the issue. Remember to perform a thorough inspection and testing of the suspension height sensor, wiring, connectors, and suspension control module, if needed, to get your vehicle back in optimal condition.

About author


Meet Sam Mitchell, your experienced and reliable guide in the complex world of car fault codes. With a robust career spanning over 15 years as a professional car mechanic, John has the skills, knowledge, and practical experience to help you navigate car fault issues with confidence.


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