C1738 DTC Code: Understanding the Fault and Possible Solutions


In the world of automotive diagnostics, DTC codes play a significant role in identifying and resolving issues with vehicles. One such code is the C1738 DTC code, which refers to a specific fault that requires attention. In this article, we will delve deep into the C1738 DTC code, understanding its meaning, potential causes, and possible solutions. So, buckle up and let’s explore!

Understanding the C1738 DTC Code

The C1738 DTC code is a diagnostic trouble code that relates to the suspension system of a vehicle. More specifically, this code is associated with a fault in the suspension leveling control circuit or sensor input signals. When this code appears, it indicates that there is an issue that needs to be addressed promptly to ensure optimal vehicle performance and safety.

Potential Causes of the C1738 DTC Code

Determining the root cause behind the C1738 DTC code can be a complex task. However, some common factors could contribute to the appearance of this code. Let’s explore a few potential causes:

  1. Faulty Suspension Leveling Control Circuit: One of the primary reasons for the C1738 DTC code is a malfunctioning suspension leveling control circuit. This circuit is responsible for adjusting the suspension’s height based on the vehicle’s load and driving conditions. A fault in this circuit can trigger the code.

  2. Abnormal Sensor Input Signals: The presence of inaccurate or abnormal sensor input signals can also result in the C1738 DTC code. Sensors play a crucial role in monitoring the suspension’s behavior and transmitting data to the vehicle’s control module. Any deviation from the expected sensor input can prompt this code.

  3. Wiring or Connector Issues: Faulty wiring or connector problems within the suspension system can lead to the appearance of the C1738 DTC code. Damaged or loose connections, as well as worn-out wires, can disrupt the communication between the various components, triggering the code.

Resolving the C1738 DTC Code

Addressing the C1738 DTC code requires a systematic approach to identify and rectify the underlying issue. Here are some potential solutions that can help resolve the problem effectively:

Solutions for Faulty Suspension Leveling Control Circuit

  • Inspect the wiring harness and connectors associated with the suspension leveling control circuit. Look for any signs of damage, corrosion, or loose connections. If any issues are found, repair or replace the affected parts accordingly.
  • Check the suspension control module for any visible damage or internal faults. If necessary, replace the control module and reprogram it as per the manufacturer’s instructions.
  • Perform a comprehensive diagnostic scan using suitable diagnostic equipment to identify specific faults within the suspension leveling control circuit. Follow the recommended troubleshooting procedures to rectify the identified issues effectively.

Solutions for Abnormal Sensor Input Signals

  • Conduct a thorough inspection of the suspension sensors, such as the ride height sensors or position sensors. Ensure that they are properly mounted, free from debris, and functioning as expected. Replace any faulty sensors to restore proper functionality.
  • Calibrate the suspension sensors according to the manufacturer’s specifications. This step may involve following a specific sequence of actions or using specialized calibration tools. Consult the vehicle’s service manual or reach out to a qualified technician for guidance.

Solutions for Wiring or Connector Issues

  • Carefully examine all the wiring connections and harnesses within the suspension system. Look for any signs of wear, damage, or loose connections. Repair or replace any affected wiring components to restore proper functionality.
  • Ensure that all connectors are securely fastened and properly seated. Apply dielectric grease to the connectors to prevent corrosion and ensure reliable electrical connections.
  • Perform a detailed inspection of the suspension-related fuses and relays. Replace any blown fuses or malfunctioning relays with suitable replacements.

Frequently Asked Questions

Q1: Can I continue driving my vehicle with the C1738 DTC code? A1: It is generally not recommended to drive your vehicle with an active DTC code, including the C1738. The presence of this code indicates an issue within the suspension system, which can affect vehicle stability, handling, and safety. It is advisable to address the problem promptly to avoid further complications.

Q2: Will resetting the DTC codes resolve the C1738 code permanently? A2: Simply clearing the DTC codes without addressing the underlying issue will not permanently resolve the C1738 code. Resetting the codes may temporarily eliminate the warning light or message, but if the underlying problem persists, the code will likely reappear. It is essential to diagnose and rectify the root cause of the code to ensure a long-term solution.

Q3: Can I fix the C1738 DTC code myself, or should I consult a professional mechanic? A3: While some basic troubleshooting steps can be performed by vehicle owners, resolving the C1738 DTC code often requires a thorough understanding of the suspension system and expertise in diagnostics. It is advisable to consult a qualified mechanic or a certified automotive technician who can accurately diagnose the problem and perform the necessary repairs using specialized equipment.


The C1738 DTC code serves as an important indicator of a fault within the suspension system. By understanding the potential causes and implementing the appropriate solutions, you can effectively address the issue. Remember, while basic troubleshooting may be possible, it is best to rely on the expertise of professionals to ensure a comprehensive and long-lasting resolution. Stay proactive, prioritize safety, and maintain the optimal performance of your vehicle.

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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