As a Cat® equipment owner, understanding common Cat fault codes can help you proactively care for your equipment and prevent serious complications. By knowing just what a specific fault code means, you can schedule the right maintenance and repairs to keep your machines in top shape. Fortunately, the Cat Central App makes it easy to identify, troubleshoot and address fault codes quickly, helping you extend your equipment’s life span and prevent machine downtime.
Understanding Cat Fault Codes
A Cat fault code is a diagnostic code that identifies complications within a machine’s system. Modern vehicles and machines contain onboard diagnostic systems to monitor components and alert owners when complications are detected. Diagnostic trouble codes (DTCs) notify you of issues within your machine so you can address them quickly before they cause further complications.
If you or your company use a telematics or fleet manager software system, each machine’s onboard diagnostics system sends DTCs to your technician or fleet manager in real time. This technology can help you manage your fleet more efficiently.
Each DTC relates to a specific fault within a vehicle or machine. The diagnostics computer inside the machine activates the corresponding code as soon as it detects an issue, and it provides information you can use to determine the best course of action and locate the nearest service center.
How Are Cat Fault Codes Generated?
Advanced technology allows heavy equipment to connect to telematics systems and relay important data. When the system detects any abnormality or faulty performance, it generates the precise code related to that complication.
How to Interpret DTCs
Each DTC is a letter followed by five numbers, and each part of the code represents a specific detail about your machine’s complication. When you see a DTC, it will feature the following elements:
Letter
A standard DTC’s first character is usually a letter, and it indicates which part of a vehicle needs attention. Each code features one of the following letters:
- B: B stands for “body” in a DTC. It indicates that the vehicle’s affected part is in the machine or vehicle’s passenger compartment area.
- C: A DTC starting with C indicates there’s an issue with the chassis. This category refers to a vehicle’s mechanical functions and systems such as the steering, braking and suspension.
- P: When a code starts with P, it means there’s a complication with the machine’s powertrain. This could indicate an issue with the transmission, engine or related accessories.
- U: A DTC starts with U when there’s a network and vehicle integration issue. This is related to the functions that the onboard computer system manages.
First Number
A DTC’s second character is a number, and it’s usually one or zero. One indicates the code is manufacturer-specific or enhanced. Zero is a generic code, which is also known as a global or standardized code.
Second Number
If the DTC you see starts with P for the powertrain system, the third character in the code indicates which subsystem needs attention. The following numbers refer to various systems and controls:
- Zero: If the second number in a DTC is zero, there’s a complication in the machine’s auxiliary emission controls and fuel and air metering system.
- One: One indicates an issue with a machine’s fuel and air metering system.
- Two: Two indicates there’s a complication with the machine’s injector circuit.
- Three: When three is the second number in a code, it means there are misfires or another issue with the ignition systems.
- Four: A code with four as its second number indicates a complication with the machine’s auxiliary emission controls.
- Five: If a code’s second number is five, a machine’s auxiliary inputs, idle control system, and speed control require attention.
- Six: Six indicates an issue with a machine’s computer system and output circuit.
- Seven: If you see seven as a code’s second number, your machine’s transmission requires attention.
While the third character in a code is typically a second number, you may see a letter instead. If you see the letter A, B, or C, you should check your machine’s hybrid propulsion system. Additionally, your machine’s manufacturer manual may list specific code sequences.
Third and Fourth Numbers
The final part of a code is a number from zero to 99 that indicates the precise complication affecting your machine. This part of a DTC is less generic than the first characters because it relates to your machine manufacturer’s specific numbers for each complication. A DTC’s final numbers are usually specific to the machine, so using your manufacturer’s diagnostic software is important.
Types of Cat Fault Codes
To further understand Cat fault codes, familiarize yourself with the following categories:
Critical
A critical code indicates your machine or vehicle has a complication that could quickly cause significant damage. When a critical code such as low coolant levels and high engine temperatures comes through, it means engine failure is probable.
Responding to a critical code as soon as possible is crucial, and you can use the machine’s diagnostics system to assess the complication’s severity and determine the best course of action before it causes further damage.
Non-Critical
Non-critical codes indicate that a less urgent issue is affecting your machine or vehicle. However, you should still make it a point to address the problem promptly. Non-critical codes are the same ones that trigger the “Check Engine” light or “Malfunction Indicator Lamp” to turn on.
Common Cat Fault Codes and Their Meanings
Understanding common Cat fault codes can help you prevent and prepare for potential repair needs. The most common Cat fault codes are related to the following types of complications:
Misfiring
A misfiring code indicates a vehicle or machine’s engine has misfired. Engine misfires can affect equipment in the following ways:
- Wear and damage: Misfires can damage machine components such as cylinders and fuel injectors.
- Imbalanced operation: A misfiring engine often operates unevenly, affecting the equipment’s overall health.
- Decreased efficiency: Misfires can impact your machine’s power and efficiency, reducing the engine’s effectiveness in converting fuel to mechanical energy.
- Shorter engine life span: Preventing and addressing engine misfires can help your engine last longer.
If your engine misfires, you may need to perform or schedule one of the following repairs:
- Fuel injector cleaning and maintenance
- Spark plug or ignition coil replacement
- Compression level testing and adjustment
- Air-fuel mixture tune-up
It’s also important to follow safety regulations if an engine misfires.
Low Oil Pressure
When your equipment telematics reveals a low oil pressure code, it means your vehicle or equipment has an inadequate amount of lubricant moving through its system.
Lubricant protects your engine from metal-on-metal friction, and addressing low oil pressure is crucial for preventing engine failure and component wear. You should respond to a low oil pressure code as soon as possible — an engine can shut down within minutes or hours if excessive friction occurs. If you encounter this type of code, turn your equipment off immediately and restore the proper oil levels or schedule repairs.
High Engine Temperature
High engine temperature can cause your equipment’s engine oil temperature to spike. An engine’s oil viscosity lowers as its temperature rises, which thins it and causes poor lubrication. You can prevent engine overheating with the following tips:
- Maintain proper coolant levels: Coolant helps manage your engine’s temperature, preventing it from boiling or freezing. Inspecting the engine daily and restoring low coolant levels can help prevent overheating.
- Keep the engine clean: Removing dirt and debris from the engine’s space outside its radiator core and between the radiator panels helps the engine maintain proper temperatures.
- Pay close attention to your equipment’s temperature gauges: It’s important to avoid pushing equipment past its limit, so you should check your owner’s manual for each machine’s recommended load and monitor temperature gauges. If the temperature exceeds the recommended limit, turn the engine off immediately. To prevent serious injury, avoid removing the radiator cap until the system cools.
Maintaining proper engine temperatures can help you prevent component wear and extend your engine’s life span. Respond to a high engine temperature fault code immediately to protect your equipment.
Hydraulic System Issues
Several types of complications can cause hydraulic system issues, so you may encounter one of the following repair needs if a hydraulic system fault code appears:
- Extreme temperatures: Excessive heat or cold can cause hydraulic system complications such as fluid oxidation, thickening and thinning.
- Water or air contamination: System breaches, excessive temperatures or faulty pumps can cause cavitation or aeration. Cavitation occurs when air contamination causes a pump to pull out dissolved air and implode, and aeration happens when the pump cavity takes in air from the outside. Condensation and system leaks can lead to water contamination, gradually degrading hydraulic components. Addressing these issues promptly is important for preventing further pump and component damage.
- Low fluid levels or fluid contamination: Adequate hydraulic fluid levels, proper filtration and fluid quality are essential for preventing air contamination, fluid contamination, leaks, temperature issues and wear. You can help prevent hydraulic system fault codes by using the correct types of hydraulic fluids for your equipment, and using anti-foam and anti-wear additives.
- Installation and maintenance errors: Human error can also cause hydraulic system complications. Incompatible components, faulty installations and improper usage or maintenance can cause hydraulic systems to malfunction or fail.
To troubleshoot issues associated with a hydraulic system fault code, you can check your equipment’s pump, motor, fluids, filters, seals, valves, and lines. You can also run your system to check for abnormal sounds, pressure or temperature fluctuations to locate the precise problem area.
Electrical System Faults
A piece of equipment’s electrical system is an essential part of its operation and longevity. Electrical components convert engine power to electricity, turn over diesel engines, and power onboard systems. The following complications are the most common triggers for electrical system fault codes:
- Alternator complications: A faulty alternator affects a machine’s onboard systems that run on electricity, causing components such as lights to stop working.
- Dead battery: A dead battery prevents a piece of equipment’s engine, dashboard, lights, and electrical systems from turning on. Proper battery storage and replacement can prevent you from experiencing a dead battery. You should also check to ensure lights are off when your equipment is not in use to prevent the battery from dying.
- Faulty starter: With a faulty starter, your engine may not start or crank, or it may crank slower than usual. You may also notice a burning odor, intermittent starting or a clicking sound when you try to start your engine.
Addressing minor electrical complications before they cause serious issues is essential for preventing complete electrical failure. Check your systems or schedule a professional inspection as soon as you receive an electrical system fault code or notice signs such as dimmed lights, intermittent starting, unusual humming sounds or dashboard warning lights.
Tools Needed for Troubleshooting
Troubleshooting your machine’s maintenance and repair needs requires diagnostic software from your machine’s manufacturer. Most diagnostic codes are unique to a specific machine, so using the right tools ensures you diagnose and address the correct issues. In traditional heavy construction equipment, you can use a diagnostic 9-pin or 14-pin adapter to find fault codes.
You can also diagnose complications in a Cat machine quickly and easily with the Cat Central App. The Cat Central App places all of the fault code definitions you need in the palm of your hand, providing you with a smooth maintenance and repair process that helps you save time and money.
When you open the app on your device, you can select the fault code look-up section and enter the code that your equipment shows. After entering the code, tap “Look Up Code” at the bottom to receive the exact definition. If your search brings up a CDL or J1939 code, tap the headset icon in the top-right corner. This connects you with a helpful Cat Customer Care representative for further support.
Using a Cat Diagnostic Adapter
You can use a Cat diagnostic adapter in the following steps:
1. Connect
Your piece of Cat equipment contains a diagnostic port. Connect your adapter to this port and turn the adapter on to establish a secure connection.
2. Launch
Launch the Cat diagnostic software on your desktop computer, or download the app on your mobile device. Use your manufacturer’s manual to configure the software settings correctly and install the proper drivers.
3. Establish a Communication Connection
Use the same manual to determine the proper communication protocol between your equipment and the diagnostic tool. This step establishes a connection so your machine can communicate with the diagnostic tool and deliver information to your software.
4. Navigate the Software
Become familiar with your diagnostic software, and locate the diagnostic menu. The most important parts of your user interface to locate are the options to retrieve codes and view logged and active codes.
5. Retrieve and Interpret the Fault Codes
Addressing fault codes immediately is essential, so you should check your software frequently to retrieve codes. Refer to your manual or online tools to interpret specific codes and gather information such as the following:
- Complication descriptions
- Possible causes
- Recommended repairs and troubleshooting tips
Troubleshoot Fault Codes Quickly and Easily With the Cat Central App
Fault codes reveal essential information about your equipment’s health and operation, enabling you to take fast action to keep your fleet running effectively. The Cat Central App makes it easy to understand and troubleshoot fault codes so you can maintain your equipment while saving time and money. With this app, you can use a fault code lookup feature to access code definitions and 24/7 Cat Customer Care service.
Browse our wide selection of Cat construction equipment, and download the Cat Central App to manage your fleet efficiently!