What is OBD-II Code P25AF – Coolant Temperature Control Module Requested MIL Illumination



What is OBD-II Code P25AF – Coolant Temperature Control Module Requested MIL Illumination

When it comes to car maintenance, there’s always something to keep track of. Automobiles today are designed with complex systems that require specialized attention, and when they malfunction, the engine’s onboard computer signals the driver through a series of alerts. One such warning is the OBD-II code P25AF – Coolant Temperature Control Module Requested MIL Illumination.

As a mechanic, I often get asked about what these codes mean and how to repair them. In this article, I will discuss what OBD-II code P25AF means and some of the possible reasons behind it.

What is OBD-II Code P25AF?

OBD-II stands for on-board diagnostic, second generation. This system is responsible for monitoring and testing the engine’s various subsystems, including the fuel injection, exhaust, ignition, and emissions systems. It’s constantly reading the gauges of your car to ensure everything’s working as it should.

Code P25AF indicates that the coolant temperature control module has requested the malfunction indication light (MIL) to be illuminated. In other words, it means that the computer has detected a problem with the coolant temperature control module and wants to notify you of the issue.

The coolant temperature control module is responsible for monitoring and regulating the temperature of the coolant in your car’s engine. It receives input from various sensors and uses that data to open and close the thermostat, ensuring that your engine stays at the right temperature.

What Causes OBD-II Code P25AF?

There are several possible causes of OBD-II code P25AF, including:

1. Faulty coolant temperature control module: This is the most common cause of the problem. If the module is malfunctioning or failing, the computer will detect it and illuminate the MIL.

2. Wiring issues: Wiring problems can cause the computer to misread the signals from the coolant temperature control module, leading to incorrect readings and the illumination of the MIL.

3. Sensor problems: Problems with the sensors that send data to the coolant temperature control module can also cause the MIL to turn on.

How to Fix OBD-II Code P25AF?

The first step in fixing OBD-II code P25AF is to identify the cause of the problem. As mentioned earlier, there are several possible causes, so it’s crucial to do a thorough diagnostic before making any repair. Here are the steps to fixing the problem:

1. Check the wiring: Start by checking the wiring connected to the coolant temperature control module. Look for any signs of damage, such as cuts, fraying, or corrosion. Repair or replace any damaged wiring.

2. Check the sensors: Next, inspect the sensors that send data to the coolant temperature control module. Make sure they’re clean and securely connected.

3. Check the module: If neither the wiring nor the sensors are the issue, the problem could be in the coolant temperature control module itself. Have it tested by a professional to determine whether it should be repaired or replaced.

Case Study

A client brought their car into my shop after noticing that the MIL was on. When I connected the OBD-II scanner, I found code P25AF. After checking the wiring and sensors, I determined that the coolant temperature control module was the issue. I replaced the faulty module, and the MIL turned off, indicating the problem was fixed.

Conclusion

When your car’s warning lights illuminate, it’s essential to take them seriously and have a mechanic diagnose and repair the problem. OBD-II code P25AF is an indication that there’s a problem with the coolant temperature control module, which regulates the temperature of your engine. If you notice this code, have your car evaluated by a professional to identify and fix the issue.

FAQs

Q: What does MIL stand for?
A: MIL stands for “malfunction indication light.” It’s the warning light on your dashboard that indicates that there is a problem with your car’s engine.

Q: Can I still drive my car if the MIL is on?
A: It’s not advisable to drive your car when the MIL is on. While minor problems with your car’s engine won’t necessarily cause immediate issues, more severe problems can cause significant damage if not addressed promptly.

Q: Can I reset the MIL by disconnecting the battery?
A: Disconnecting the battery won’t reset the MIL. It’s important to have your car diagnosed and repaired by a professional mechanic to avoid further problems.

Q: How much does it cost to repair code P25AF?
A: The cost of repairing code P25AF varies depending on the extent of the problem and the parts and labor required to fix it. It’s best to have a professional mechanic evaluate your car to determine the cost of repairs.

Q: Is it safe to continue driving my car with code P25AF?
A: It’s not advisable to drive your car when the MIL is on. Even if your car continues to operate normally, ignoring warning lights can lead to more severe problems down the road.

20% off Additional Services at Valvoline Instant Oil Change

20% off Cabin Air Filter Replacement at Valvoline Instant Oil Change

Scroll to Top