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Harley Code P2602: Understanding the Diagnostic Trouble Code

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Chase Manhattan

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Owner and Editor at The Wrench Network

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Hey y’all, it’s Chase Manhattan! I’m a life-long automotive and motorcycle enthusiast with a knack for diagnostics that I hope to share with you! Lately, I’ve been running my own motorcycle rental business, which you can read about here, and it has been a great experience that has allowed me to own numerous bikes that I probably couldn’t justify otherwise. Plus, it’s been a great way to experience new places while on vacation. If you haven’t heard of them before, I definitely recommend checking out the Riders-Share platform if you get the itch to ride while away from home, or if you want to explore a cheaper way to own and ride motorcycles!

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If you own a Harley Davidson motorcycle and have been experiencing issues with the engine coolant pump control circuit, then you may have encountered the P2602 error code. This code is related to low voltage in the coolant pump circuit and can be a frustrating issue for riders to deal with. However, with the right knowledge and troubleshooting steps, it is possible to fix this problem and get back to enjoying your ride.

When dealing with the P2602 error code, it is important to start with a visual inspection of the wiring harness and connectors. Look for any damaged components or connector pins that may be causing the low voltage issue. Additionally, checking the coolant pump itself to ensure it is functioning properly can be helpful in diagnosing the problem. With these steps and the help of a trusted mechanic if needed, you can get your Harley back on the road in no time.

Understanding Harley Code P2602

If you are an owner of a Harley-Davidson motorcycle and have encountered the P2602 code, you may have some questions about what it means and how to fix it. In this section, we will provide you with a technical description of the code and its OBD-II trouble code.

Technical Description

The P2602 code is a diagnostic trouble code (DTC) related to the coolant pump control circuit. This code is set when the Engine Control Module (ECM) detects a low voltage signal from the coolant pump control circuit. The ECM uses this signal to control the coolant pump operation.

The coolant pump is responsible for circulating coolant through the engine and radiator to keep the engine at a safe operating temperature. When the ECM detects a low voltage signal from the coolant pump control circuit, it may activate the Check Engine Light (CEL) and store the P2602 code in its memory.

OBD-II Trouble Code

The P2602 code is a generic OBD-II trouble code that applies to all vehicles equipped with OBD-II systems, including Harley-Davidson motorcycles. The code is triggered when the ECM detects a low voltage signal from the coolant pump control circuit.

If you encounter the P2602 code, the first step is to visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins. If you find any issues, repair or replace them as necessary.

If the wiring and connectors appear to be in good condition, you may need to replace the coolant pump. It is also possible that the ECM itself is faulty, but this is less common.

In summary, the P2602 code is related to the coolant pump control circuit and indicates a low voltage signal. If you encounter this code, check the wiring and connectors first, and then consider replacing the coolant pump if necessary.

Possible Causes and Diagnostics

If you have a Harley motorcycle and you are experiencing the P2602 code, there are a few possible causes that you should be aware of. In this section, we will discuss the most common causes of the P2602 code and provide some diagnostic tips to help you identify and fix the problem.

Electrical Issues

One of the most common causes of the P2602 code is an electrical issue. This could be a problem with the wiring harness, wires, connectors, or corroded connector pins. To diagnose an electrical issue, you will need to visually inspect the related wiring harness and connectors. Look for broken, bent, pushed out, or corroded connector pins. If you find any damaged components, replace them as needed.

Coolant Pump Failures

Another possible cause of the P2602 code is a faulty coolant pump. If the coolant pump is not working properly, it can cause a low voltage concern in the coolant pump control circuit. To diagnose a coolant pump failure, you will need to check the pump for proper operation. You can do this by checking the pump’s resistance with a multimeter. If the resistance is not within the manufacturer’s specifications, the pump will need to be replaced.

PCM and Circuit Problems

Finally, the P2602 code can also be caused by problems with the PCM and circuit. This could be a problem with the coolant pump relay or the electrical grease used to connect the relay and wiring. To diagnose a PCM or circuit problem, you will need to check the relay and wiring for proper operation. You can do this by checking the resistance of the relay and the continuity of the wiring. If you find any issues, replace the faulty components as needed.

In conclusion, the P2602 code can be caused by a variety of issues, including electrical issues, coolant pump failures, and PCM and circuit problems. By following the diagnostic tips provided in this section, you can identify and fix the problem quickly and easily.

Troubleshooting Steps

If you are experiencing the P2602 code on your Harley, you need to take some troubleshooting steps. These steps will help you diagnose the problem and get your bike running smoothly again. Here are some of the initial inspections and advanced diagnostics you can perform:

Initial Inspection

The first step in troubleshooting the P2602 code is to inspect the coolant pump and its wiring. Check for any signs of damage or wear and tear. Look for any loose connections or broken wires. If you find any issues, you will need to repair or replace the affected parts.

Next, check the coolant level in your bike. Low coolant levels can cause the P2602 code to appear. If the coolant level is low, you will need to top it up.

Advanced Diagnostics

If the initial inspection did not reveal any issues, you will need to perform some advanced diagnostics. The following steps will help you diagnose the problem:

  1. Use a diagnostic tool to read the diagnostic trouble codes (DTCs) stored in your bike’s onboard computer. This will help you identify any other issues that may be causing the P2602 code.

  2. Inspect the coolant pump relay and its wiring. Look for any signs of damage or wear and tear. Check for any loose connections or broken wires. If you find any issues, you will need to repair or replace the affected parts.

  3. Test the coolant pump using a multimeter. This will help you determine if the pump is functioning properly. If the pump is not working correctly, you will need to replace it.

  4. Check the engine coolant temperature sensor. If this sensor is faulty, it can cause the P2602 code to appear. Use a multimeter to test the sensor and replace it if necessary.

  5. Inspect the engine control module (ECM) and its wiring. Look for any signs of damage or wear and tear. Check for any loose connections or broken wires. If you find any issues, you will need to repair or replace the affected parts.

By following these troubleshooting steps, you should be able to diagnose and fix the P2602 code on your Harley. If you are still experiencing issues after performing these steps, it is recommended that you take your bike to a professional mechanic for further diagnosis and repair.

Repair and Solution

If you’re experiencing Harley code P2602, it’s important to address the issue as soon as possible. Here are some solutions and repairs to help you fix the problem.

Addressing Electrical Issues

One possible cause of P2602 is related to electrical issues. If you suspect this is the case, you can try to fix it by checking the wiring harness and connectors. Visually inspect the related wiring harness and connectors to make sure they are in good condition. If you see any damage or corrosion, replace the damaged parts.

To clean the electrical contacts, you can use electrical contact cleaner. This will help remove any dirt or debris that may be causing the problem. Spray the cleaner onto the contacts and let it sit for a few minutes. Then, use a clean cloth to wipe away any excess cleaner.

Coolant Pump Replacement

If the above solution doesn’t work, you may need to replace the coolant pump. This is a more involved process, but it can be done with the right tools and some mechanical knowledge. You can find replacement pumps online or at your local auto parts store.

Before you start the replacement process, make sure you have the right tools on hand. You’ll need a socket set, pliers, and a torque wrench. You’ll also need to drain the coolant from the system.

To replace the pump, start by removing the old pump and disconnecting the electrical connections. Then, install the new pump and reconnect the electrical connections. Finally, refill the coolant system and check for leaks.

The repair importance level for P2602 is 3/3, which means it’s a critical issue that needs to be addressed as soon as possible. The repair difficulty level is also 3/3, which means it’s a complex repair that requires some mechanical knowledge and the right tools.

Preventive Maintenance

Regular maintenance is essential to keep your Harley in good running condition and prevent problems like code P2602 from occurring. Here are some preventive measures you can take to keep your cooling system in good shape.

Regular Check-Ups

Regular check-ups are important to ensure that your cooling system is functioning properly. You should have your Harley checked by a qualified technician at least once a year. During the check-up, the technician will inspect the cooling system for leaks, cracks, and other damage. They will also check the coolant level and the condition of the hoses and belts.

Protective Measures

Protective measures can help prevent code P2602 from occurring. Here are some things you can do to protect your cooling system:

  • Check the coolant level regularly and top it up as needed.
  • Check the condition of the hoses and belts and replace them if they are worn or damaged.
  • Make sure the cooling system is free of leaks and cracks.
  • Use the recommended coolant for your Harley. Using the wrong type of coolant can cause damage to the cooling system.
  • Avoid riding your Harley in extreme temperatures. High temperatures can cause the cooling system to work harder than normal, which can lead to problems.

By taking these preventive measures, you can help keep your Harley running smoothly and prevent problems like code P2602 from occurring.

Understanding Related Codes

If you’re experiencing Harley code P2602, there are a few other related codes you should be aware of. These codes can help you diagnose the issue and get your bike back on the road as quickly as possible.

Code P2600 and P2603

Code P2602 is part of a group of codes related to the coolant pump circuit. Two other codes in this group are P2600 and P2603. P2600 means that the coolant pump control circuit is open, while P2603 means that the circuit is shorted to ground.

If you’re seeing either of these codes along with P2602, it’s likely that there’s an issue with the wiring or connectors related to the coolant pump circuit. You should visually inspect the wiring harness and connectors for any damage or corrosion. Look for broken, bent, or pushed-out connector pins, and check for damaged components.

Other Coolant Pump Codes

There are a few other codes related to the coolant pump circuit that you might see alongside P2602. These codes include P2601, P261A, P261B, P261C, and P261D.

P2601 means that the coolant pump “B” control circuit is low. This is similar to P2602, but it relates to a different coolant pump circuit. P261A, P261B, P261C, and P261D all relate to the coolant pump relay control circuit. If you’re seeing any of these codes, it’s likely that there’s an issue with the wiring or connectors related to the coolant pump circuit.

In summary, if you’re seeing Harley code P2602 along with any of these other related codes, it’s likely that there’s an issue with the wiring or connectors related to the coolant pump circuit. You should visually inspect the wiring harness and connectors for any damage or corrosion, and look for broken, bent, or pushed-out connector pins. By doing so, you can quickly diagnose the issue and get your bike back on the road.

Model-Specific Concerns

Harley-Davidson Specifics

If you own a Harley-Davidson motorcycle and are experiencing the P2602 code, there are some model-specific concerns you should be aware of. The coolant pump control circuit low code can be caused by a variety of issues, including a malfunctioning coolant pump, a faulty PCM, or a wiring issue.

One potential issue specific to Harley-Davidson motorcycles is a faulty fan control module. If your bike is equipped with this module and you are experiencing the P2602 code, it may be worth checking the module to see if it is functioning properly.

Another potential issue specific to Harley-Davidson motorcycles is a faulty engine temperature sensor. If the sensor is not reading the engine temperature correctly, it may be causing the coolant pump to run too often or not enough, resulting in the P2602 code.

Other Brands and Code P2602

While the P2602 code is most commonly associated with Harley-Davidson motorcycles, it can also occur in other brands, such as Ford, Audi, Honda, Nissan, and Toyota. If you own a vehicle from one of these brands and are experiencing the P2602 code, there are a few model-specific concerns you should be aware of.

For example, some Ford vehicles may experience the P2602 code along with the B1103, B1153, B1200, B1210, or B1211 codes. These codes may indicate a wiring issue or a faulty PCM, and may require further diagnosis to determine the root cause of the problem.

Similarly, some Honda vehicles may experience the P2602 code along with other codes related to the coolant system, such as the P0128 code. This may indicate a faulty thermostat or a malfunctioning coolant temperature sensor.

It is important to note that the P2602 code can have many different causes, and it is always best to have a professional diagnose and repair the issue. If you are experiencing the P2602 code, it is recommended that you take your vehicle to a trusted mechanic or dealership for further diagnosis and repair.

Professional Assistance and Resources

If you are experiencing trouble with Harley code P2602, there are a few resources and options available to you for professional assistance. This section will cover some of those options.

Technical Service Bulletins

Before seeking expert help, it is important to check if there are any Technical Service Bulletins (TSBs) related to the P2602 code. TSBs are issued by the manufacturer when there is a known issue with a particular model or component. Checking for TSBs can help you determine if the issue you are experiencing is widespread and if there are any known fixes or workarounds.

To find TSBs for your Harley, you can check the manufacturer’s website or consult with a trusted mechanic. It is important to note that TSBs are not the same as recalls, and you may be responsible for any repairs or fixes required.

Seeking Expert Help

If you are unable to resolve the P2602 code on your own, seeking expert help is the next step. There are several options available to you, including:

  • Independent Mechanics: Independent mechanics can be a great resource for Harley owners, as they often have experience working specifically with Harley models. You can find independent mechanics in your area by searching online or consulting with fellow Harley owners.

  • Dealerships: Harley dealerships are another option for expert help. Dealerships have access to manufacturer-specific tools and resources, and their technicians are trained specifically on Harley models. However, dealership services can be more expensive than independent mechanics.

  • Failed PCM: If the P2602 code is caused by a failed PCM, you may need to replace the component entirely. This is a more complex repair that should be handled by a professional. In this case, it is recommended to consult with a dealership or trusted mechanic.

Remember to always consult with a trusted expert before attempting any repairs on your own. Harley codes can be complex and difficult to diagnose, and attempting repairs without the proper knowledge and tools can lead to further damage.

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