17525/P1117 DTC Code: Causes, Symptoms, and Solutions


In the world of automotive diagnostics, trouble codes play a crucial role in identifying and resolving issues within a vehicle. One such code is the 17525/P1117 DTC code. In this comprehensive guide, we will delve deep into this specific code, exploring its causes, symptoms, and possible solutions. So let’s get started!

Understanding the 17525/P1117 DTC Code

What does it mean?

The 17525/P1117 DTC code refers to a fault detected in the Engine Coolant Temperature (ECT) sensor circuit. This fault is categorized as a “high” signal issue. It usually indicates that the actual engine coolant temperature is higher than expected or that there may be a problem with the sensor or its wiring.

What are the causes?

There are several potential causes for the 17525/P1117 DTC code. Some of the most common include:

  1. Faulty Engine Coolant Temperature (ECT) sensor: A malfunctioning sensor may provide incorrect readings, triggering the DTC code.
  2. Wiring issues: Damaged or loose connections between the ECT sensor and the Engine Control Module (ECM) can cause erratic signals and result in this code.
  3. Cooling system problems: Issues such as low coolant levels, a malfunctioning thermostat, or a faulty water pump can all contribute to abnormal engine temperatures and trigger the code.
  4. ECM failure: In rare cases, a failure in the ECM itself can result in the DTC code.

Symptoms of the 17525/P1117 DTC Code

When the 17525/P1117 DTC code is triggered, you might experience one or more of the following symptoms:

  1. Illuminated Check Engine Light (CEL): The CEL is designed to notify the driver of potential issues in the vehicle’s systems. When this code is present, the CEL will likely remain lit until the problem is resolved.
  2. Engine overheating: If the ECT sensor provides incorrect readings, it can lead to engine overheating, which requires immediate attention to prevent further damage.
  3. Reduced engine performance: You might notice a decrease in engine power or poor acceleration, as the ECM adjusts certain parameters to protect the engine from potential harm caused by overheating.

Diagnosing and Resolving the 17525/P1117 DTC Code

When faced with the 17525/P1117 DTC code, it is essential to follow a systematic approach to diagnose and resolve the issue. Here are the steps you should take:

  1. Scan the vehicle for other trouble codes: Sometimes, multiple codes can be triggered simultaneously. Checking for additional codes can provide valuable clues about the underlying problem.
  2. Inspect the coolant level: Ensure that the coolant level is within the specified range. If it is low, top it up and monitor for any potential leaks in the system.
  3. Check the ECT sensor and wiring: Inspect the ECT sensor for any signs of damage or corrosion. Also, examine the wiring harness and connectors for any visible issues. Repair or replace them as necessary.
  4. Test the ECT sensor: Using a multimeter, measure the resistance of the ECT sensor at different temperatures. Compare the readings with the manufacturer’s specifications to determine if the sensor is functioning correctly.
  5. Check the thermostat and water pump: If the ECT sensor and wiring are in good condition, inspect the thermostat and water pump for any faults. Replace any components that are not functioning properly.
  6. Clear the trouble code and monitor the system: After resolving the issue, clear the trouble code using an appropriate diagnostic tool. Then, monitor the vehicle to ensure the code does not reappear during normal operation.

Frequently Asked Questions (FAQs)

Q1: Can I drive my vehicle with the 17525/P1117 DTC code?

It is generally not recommended to drive your vehicle with the 17525/P1117 DTC code, especially if you notice symptoms such as engine overheating. Continuing to drive without resolving the issue can potentially cause further damage to the engine.

Q2: Can a faulty ECT sensor cause poor fuel efficiency?

Yes, a faulty Engine Coolant Temperature (ECT) sensor can lead to poor fuel efficiency. If the sensor provides incorrect readings, the engine may not receive the optimal fuel-air mixture, resulting in reduced efficiency and increased fuel consumption.

Q3: How much does it cost to fix the 17525/P1117 DTC code?

The cost of fixing the 17525/P1117 DTC code can vary depending on the cause of the issue and the labor rates of your chosen repair facility. In general, it can range from a simple sensor replacement (around $50-$100 for the part) to more complex repairs involving the thermostat, wiring, or ECM, which can cost several hundred dollars.

Remember, these are just general estimates, and the actual cost can vary significantly based on various factors. It is always recommended to consult a qualified mechanic or technician for an accurate diagnosis and cost estimation.


The 17525/P1117 DTC code can be a cause for concern, indicating a problem with the Engine Coolant Temperature (ECT) sensor circuit. By understanding the causes, symptoms, and diagnostic steps discussed in this article, you can tackle this code effectively. Remember, timely diagnosis and resolution are essential to maintain the performance and longevity of your vehicle. When in doubt, seeking professional assistance is always a wise decision.

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.


Leave a Reply