AutoCodes – GMC – P25AF 2018 GMC Sierra

P25AF 2018 GMC Sierra Code - Coolant Temperature Control Module Requested MIL Illumination

Quick Answer

Control modules constantly monitor the vehicle for any condition which may adversely affect vehicle performance. Common causes include Check Coolant Temperature Control Module for codes, Faulty Coolant Temperature Control Module. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P25AF 2018 GMC Sierra indicates Coolant Temperature Control Module Requested MIL Illumination.
Common causes: Common causes include Check Coolant Temperature Control Module for codes, Faulty Coolant Temperature Control Module.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 141

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jul 15, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P25AF 2018 GMC Sierra Description

Control modules constantly monitor the vehicle for any condition which may adversely affect vehicle performance. If a condition is detected, the module sets a Diagnostic Trouble Code (DTC) and sends a serial data message to the Engine Control Module (ECM). The ECM sets a DTC to inform that the module has set a DTC. The serial data message sent by the module also contains a request for the ECM to illuminate the Malfunction Indicator Lamp (MIL).
The DTC will be set when the ECM receives a serial data message from the Coolant Temperature Control Module indicating that DTC has been set in the module.

OBDII Code P25AF 2018 GMC Sierra - Coolant Temperature Control Module Requested MIL Illumination - AutoCodes.com — P25AF 2018 GMC Sierra Code - Coolant Temperature Control Module Requested MIL Illumination

What does this mean?

What are the Possible Causes of the DTC P25AF 2018 GMC Sierra?

Check Coolant Temperature Control Module for codes
Faulty Coolant Temperature Control Module

How to Fix the DTC P25AF 2018 GMC Sierra?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P25AF 2018 GMC Sierra code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P25AF 2018 GMC Sierra code?

Need more information on how to fix the P25AF 2018 GMC Sierra code? Get Access to Factory Service Manuals

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P25AF 2018 GMC Sierra Code

1. What are common symptoms of OBDII code P25AF in a 2018 GMC Sierra?

- Common symptoms include the Check Engine Light coming on, engine overheating, and potential issues with the cooling system.

2. What does the OBDII code P25AF indicate in a 2018 GMC Sierra?

- The code P25AF indicates a fault related to the Coolant Temperature Control Module Requested MIL Illumination in the vehicle.

3. What are possible causes of the P25AF code in a 2018 GMC Sierra?

- Possible causes include a malfunctioning coolant temperature control module, wiring issues, a faulty temperature sensor, or a problem within the cooling system.

4. How can I diagnose the P25AF code in my 2018 GMC Sierra?

- Diagnosis typically involves using an OBDII scanner to retrieve the specific code, checking the coolant temperature sensor, inspecting the wiring connections, and testing the coolant temperature control module.

5. Can I still drive my 2018 GMC Sierra with the P25AF code?

- It is not recommended to drive the vehicle with the P25AF code present, as it may lead to engine overheating and potential damage. It is best to address the issue promptly.

6. How can I repair the P25AF code in my 2018 GMC Sierra?

- Repair options may include replacing the coolant temperature control module, repairing any wiring issues, replacing the temperature sensor, or addressing any cooling system problems identified during diagnosis.

7. Is it safe to clear the P25AF code with an OBDII scanner?

- Clearing the code may temporarily turn off the Check Engine Light, but it is essential to address the underlying issue causing the code to prevent further problems with the vehicle.

8. Will the P25AF code affect the performance of my 2018 GMC Sierra?

- The P25AF code can potentially affect the performance of the vehicle, especially if it leads to engine overheating or cooling system malfunctions. It is advisable to address the issue promptly.

9. Can a DIY enthusiast repair the P25AF code in a 2018 GMC Sierra?

- Depending on the individual's skill level and access to tools, some DIY enthusiasts may be able to address the P25AF code by following repair guides and procedures specific to the GMC Sierra model.

10. How much does it cost to repair the P25AF code in a 2018 GMC Sierra?

- The cost of repairing the P25AF code can vary depending on the specific issue causing the code, the parts needed for repair, and whether the repair is done at a dealership, independent mechanic, or DIY. It is advisable to obtain quotes from different sources for an accurate estimate.