The check engine light is one of the most hated lights that can illuminate on your car’s dashboard. It signals that there is a problem with the car and it needs to be checked out. Unless you have a diagnostic tool, you may not be able to know what is happening under the hood. But once you attach your diagnostic tool and the code reads “OBD-II Code P2679 – Coolant Degassing Valve Control Circuit Low,” what does that mean?
As a mechanic, I have encountered this code and I am here to help you understand what it means and what you need to do to repair the issue.
What is OBD-II Code P2679 – Coolant Degassing Valve Control Circuit Low?
The OBD-II Code P2679 indicates that there is a malfunction associated with the coolant degassing valve control circuit. When a vehicle’s engine runs, it generates a lot of heat. This heat needs to be controlled, and the way cars do that is by using coolant. The coolant flows around the engine, drawing the heat away and taking it to the radiator, where it is dissipated into the air.
The coolant degassing valve is an essential component in the cooling system. Its job is to expel excess air out of the cooling system. Any air in the cooling system could impede coolant flow and cause the engine to overheat. It is essential to keep the system free of air to avoid such problems.
The coolant degassing valve control circuit is responsible for powering the coolant degassing valve. When the engine management system detects a fault within this circuit, it triggers the check engine light and stores the P2679 fault code in the system.
What Causes the Coolant Degassing Valve Control Circuit Low Fault Code?
The P2679 fault code can arise due to different reasons. Here are some of the common issues that may cause this problem:
1. Wiring Issues: A fault in the wiring harness that connects the coolant degassing valve to the engine control module can lead to P2679 code.
2. Coolant Degassing Valve Malfunction: If the coolant degassing valve has failed, the control circuit may not function correctly, leading to the P2679 code.
3. Bad Engine Control Module: If the engine control module (ECM) fails to provide sufficient voltage to the coolant degassing valve, it can result in the P2679 code.
4. Coolant System Blockage: If coolant is not circulating adequately through the engine, it could cause a blockage. Such blockages can restrict coolant flow and air removal from the cooling system, causing the P2679 code.
How to Repair the P2679 Code
Once you know what causes the P2679 fault code, you need to know how to fix it. The approach you will use may depend on the underlying issue. Here are some possible ways to fix it:
1. Check for Wiring Issues: The first step is to check if there is any damage to the wiring harness. If you find any breaks, damages or corroded wires, you may need to repair or replace them.
2. Test the Coolant Degassing Valve: You may need to test the coolant degassing valve to confirm if it is faulty. A multi-meter can be used to test the valve’s resistance. If the valve is faulty, it may need to be replaced.
3. Replace the Control Module: If the engine control module is faulty and causing the P2679 code, you may need to replace it. This procedure requires specialized skills, and it’s advisable to seek professional help.
4. Remove Coolant System Blockages: A blocked coolant system can cause the engine to overheat and could also be responsible for the P2679 code. You may need to flush the coolant system and replace the coolant to get rid of any dirt or grime that may cause blockages.
5. Reset the Engine Control Module: After fixing the underlying issue, it’s essential to reset the engine control module. This resets the code and allows the system to record new data. Your check engine light should go off after a successful reset.
FAQs
1. Can I Drive with a P2679 Code?
While it is possible to drive with a P2679 code, it is not advisable. The P2679 code indicates that there is a problem with your engine’s cooling system, which needs to be checked to prevent any further damage to your vehicle.
2. Can a P2679 Code be Cleared?
Yes, the P2679 code can be cleared. To clear the check engine light, you need to repair the underlying issue, then use a diagnostic tool to clear the code.
3. How Much Should I Expect to Pay to Fix a P2679 Code?
The cost of fixing a P2679 code varies depending on the underlying issue’s complexity. In some cases, fixing it may only require a few dollars, while in others, the cost may run into thousands of dollars.
4. Can I Fix a P2679 Code Myself?
If you have the technical knowledge and the right tools, you may be able to fix some P2679 codes. However, for complex issues, it’s advisable to seek professional help.
5. How Can I Prevent P2679 Code from Occurring?
The best way to prevent P2679 code from occurring is by keeping the cooling system in top condition. Regular maintenance, such as changing coolant and flushing the system, can also help prevent the issue.
Conclusion
The P2679 code is not something to be ignored. It indicates that there is a problem with the coolant degassing valve control circuit, which could cause serious engine problems if left unchecked. As a mechanic, I recommend that you fix the underlying issue as soon as possible to avoid further damage to your vehicle. Don’t hesitate to seek professional help if you are not sure how to fix the issue. Remember, regular maintenance is essential to keep your vehicle running at its best.