Diagnostics
CAT Engine Fault Codes List & Code Lookup
Look up 1,340 CAT Engine fault codes and error codes, in plain English. 199 of them have a full guide covering what the code means, what triggers it, the most common causes, and the first things to check before you call the dealer.
CAT Engine fault code guides
- 10010Engine Oil Pressure Sensor abnormal rate of change
- 10013Engine Oil Pressure calibration required
- 1003Engine Oil Pressure open/short to +batt
- 1004Engine Oil Pressure short to ground
- 10113Crankcase Air Pressure Sensor:Calibration Required
- 1013Crankcase Air Pressure Sensor : Voltage Above Normal
- 1014Crankcase Air Pressure Sensor : Voltage Below Normal
- 105Cylinder #10 Injector : Current Below Normal
- 106Cylinder #10 Injector : Current Above Normal
- 10765Engine Cooling Fan Bypass Solenoid open circuit
- 10766Engine Cooling Fan Bypass Solenoid short to ground
- 1103Engine Coolant Temperature open/short to +batt
- 1104Engine Coolant Temperature short to ground
- 111Cylinder #1 Injector fault
- 115Cylinder #11 Injector : Current Below Normal
- 116Cylinder #11 Injector : Current Above Normal
- 12Cylinder #1 Injector : Erratic, Intermittent, or Incorrect
- 125Cylinder #12 Injector : Current Below Normal
- 126Cylinder #12 Injector : Current Above Normal
- 15Cylinder #1 Injector : Current Below Normal
- 157Low Engine Oil Pressure - Warning
- 15893Turbo Inlet Air Pressure Sensor Open/Short to +Batt
- 15894Turbo Inlet Air Pressure Sensor Short to Ground
- 16Cylinder #1 Injector short
- 16275Fuel Pump Relay:Current Below Normal
- 16276Fuel Pump Relay:Current Above Normal
- 16392Machine Security System Incorrect
- 16399Machine Security System Module : Abnormal Update Rate
- 16411Injector Actuation Pressure system fault
- 1643Injector Actuation Pressure Voltage High
- 1644Injector Actuation Pressure Voltage Low
- 168High Engine Coolant Temperature - Derate
- 1680System Voltage High
- 1681System Voltage Low
- 1682System Voltage intermittent/erratic
- 1684Electrical System Voltage : Voltage Below Normal
- 17Cylinder #1 Injector : Not Responding Properly
- 1723Intake Manifold Air Temp open/short to +batt
- 1724Intake Manifold Air Temp short to ground
- 1743Fuel Temperature open/short to +batt
- 1744Fuel Temperature short to ground
- 1753Engine Oil Temperature open/short to +batt
- 1754Engine Oil Temperature short to ground
- 178510Intake Manifold Pressure Signal Abnormal Rate of Change
- 178513Intake Manifold Pressure Sensor : Calibration Required
- 178521Intake Manifold Pressure Sensor : Data Drifted Low
- 17853Intake Manifold Pressure Sensor : Voltage Above Normal
- 17854Intake Manifold Pressure Sensor : Voltage Below Normal
- 179710Fuel Rail Pressure Sensor : Abnormal Rate of Change
- 17973Fuel Rail Pressure Sensor : Voltage Above Normal
- 17974Fuel Rail Pressure Sensor : Voltage Below Normal
- 1811Fuel Control Valve : Other Failure Mode
- 1812Fuel Control Valve: Failure
- 18342Ignition Key Switch loss of signal
- 187Fuel Control Valve : Not Responding Properly
- 19011Engine Speed Sensor mechanical failure
- 1902Loss of Engine Speed Signal
- 1903Engine Speed Sensor Voltage Above Normal
- 1908Engine Speed signal abnormal
- 211Cylinder #2 Injector fault
- 213135 Volt Sensor DC Power Supply #2 : Voltage Above Normal
- 213145 Volt Sensor DC Power Supply #2 : Voltage Below Normal
- 22Cylinder #2 Injector : Erratic, Intermittent, or Incorrect
- 22466Engine Glow Plug Relay : Current Above Normal
- 24175Ether Injection Control Solenoid : Current Below Normal
- 24176Ether Injection Control Solenoid : Current Above Normal
- 2479SAE J1939 Data Link : Abnormal Update Rate
- 2489Cat Data Link not communicating
- 25Cylinder #2 Injector open circuit
- 2532Personality Module : Erratic, Intermittent, or Incorrect
- 25335Compression Brake Low/High Solenoid #1 : Current Below Normal
- 25336Compression Brake Low/High Solenoid #1 : Current Above Normal
- 25345Compression Brake Low/High Solenoid #2 current below normal
- 25346Compression Brake Low/High Solenoid #2 current above normal
- 25355Compression Brake Medium/High Solenoid #1 : Current Below Normal
- 25356Compression Brake Medium/High Solenoid #1 : Current Above Normal
- 25365Compression Brake Medium/High Solenoid #2 current below normal
- 25366Compression Brake Medium/High Solenoid #2 current above normal
- 25412Electronic Control Module Error
- 26Cylinder #2 Injector : Current Above Normal
- 26025Cylinder #1 Injector Actuator #2:Current Below Normal
- 26026Cylinder #1 Injector Actuator #2:Current Above Normal
- 26045Cylinder #2 Injector Actuator #2:Current Below Normal
- 26046Cylinder #2 Injector Actuator #2:Current Above Normal
- 26065Cylinder #3 Injector Actuator #2:Current Below Normal
- 26066Cylinder #3 Injector Actuator #2:Current Above Normal
- 26085Cylinder #4 Injector Actuator #2:Current Below Normal
- 26086Cylinder #4 Injector Actuator #2:Current Above Normal
- 26105Cylinder #5 Injector Actuator #2:Current Below Normal
- 26106Cylinder #5 Injector Actuator #2:Current Above Normal
- 26111Engine Timing Offset fault
- 26113Engine Timing Calibration required
- 26125Cylinder #6 Injector Actuator #2:Current Below Normal
- 26126Cylinder #6 Injector Actuator #2:Current Above Normal
- 26235 Volt Sensor DC Power Supply short to +batt
- 26245 Volt Sensor DC Power Supply short to ground
- 2633Digital Sensor Supply short to +batt
- 2634Digital Sensor Supply short to ground
- 2648Decel Throttle Position Signal Abnormal
- 2672Incorrect Engine Shutdown Switch inputs
- 2673Remote Shutdown Input : Voltage Above Normal
- 2674Remote Shutdown Input : Voltage Below Normal
- 2682Programmed Parameter Fault : Erratic, Intermittent, or Incorrect
- 27Cylinder #2 Injector : Not Responding Properly
- 273Turbo Outlet Pressure above normal
- 27313Turbo Outlet Pressure calibration required
- 2733Turbo Outlet Pressure open/short to +batt
- 2734Turbo Outlet Pressure short to ground
- 27383Turbocharger #1 Compressor Inlet Pressure Sensor : Voltage Above Normal
- 27384Turbocharger #1 Compressor Inlet Pressure Sensor : Voltage Below Normal
- 27413Atmospheric Pressure Sensor: Calibration Required
- 2743Atmospheric Pressure open/short to +batt
- 2744Atmospheric Pressure short to ground
- 27513Right Turbo Inlet Pressure calibration required
- 2753Right Turbo Inlet Pressure open/short to +batt
- 2754Right Turbo Inlet Pressure short to ground
- 27703Throttle Lock Resume/Decel Switch Voltage Above Normal
- 27704Throttle Lock Resume/Decel Switch : Voltage Below Normal
- 27713Throttle Lock Set/Accel Switch : Voltage Above Normal
- 27714Throttle Lock Set/Accel Switch Voltage Below Normal
- 2835Filter Restrict Lamp open/short to +batt
- 2836Filter Restrict Lamp short to ground
- 2915Engine Cooling Fan Solenoid open circuit
- 2916Engine Cooling Fan Solenoid short to ground
- 2969Unable to communicate with Transmission ECM
- 311Cylinder #3 Injector fault
- 32Cylinder #3 Injector : Erratic, Intermittent, or Incorrect
- 32011Speed/Timing Sensor Mechanical Failure
- 3202Speed/Timing Sensor Loss of Signal
- 34211Secondary Engine Speed Sensor mechanical failure
- 3422Loss of Secondary Engine Speed signal
- 3428Secondary Engine Speed Sensor : Abnormal Frequency, Pulse Width, or Period
- 35Cylinder #3 Injector : Current Below Normal
- 36Cylinder #3 Injector : Current Above Normal
- 360912Aftertreatment #1 Outlet #1 NOx Level Sensor : Failure
- 37Cylinder #3 Injector : Not Responding Properly
- 38215Aftertreatment #1 Diesel Exhaust Fluid Dosing Valve Actuator : Current Below Normal
- 411Cylinder #4 Injector fault
- 4138 Volt DC Supply short to +batt
- 4148 Volt DC Supply short to ground
- 42Cylinder #4 Injector : Erratic, Intermittent, or Incorrect
- 425Injector Actuation Valve Open Circuit
- 426Injector Actuation Valve Short to Ground
- 45Cylinder #4 Injector : Current Below Normal
- 46Cylinder #4 Injector : Current Above Normal
- 4603Fuel Pressure Sensor - After Fuel Filter : Voltage Above Normal
- 4604Fuel Pressure Sensor - After Fuel Filter : Voltage Below Normal
- 47Cylinder #4 Injector : Not Responding Properly
- 4855Engine Fan Rev Solenoid Open Circuit
- 4856Engine Fan Rev Solenoid Short to Ground
- 511Cylinder #5 Injector fault
- 52Cylinder #5 Injector : Erratic, Intermittent, or Incorrect
- 5448Engine Cooling Fan Speed signal abnormal
- 5455Ether Start Relay open/short to +batt
- 5456Ether Start Relay short to ground
- 5465Ether Hold Relay open/short to ground
- 5466Ether Hold Relay short to +batt
- 5485Throttle Lock Lamp open circuit
- 5486Throttle Lock Lamp short
- 5492Incorrect Throttle Lock Switch inputs
- 55Cylinder #5 Injector open circuit
- 56Cylinder #5 Injector short
- 5629Unable to Communicate with Cat Monitoring System
- 57Cylinder #5 Injector : Not Responding Properly
- 58569SAE J1939 Data Link #3:Abnormal Update Rate
- 611Cylinder #6 Injector fault
- 6176Air Inlet Heater Relay Grounded/Current Above Normal
- 62Low Engine Coolant Level Shutdown
- 65Cylinder #6 Injector : Current Below Normal
- 66Cylinder #6 Injector : Current Above Normal
- 67Cylinder #6 Injector : Not Responding Properly
- 75Cylinder #7 Injector : Current Below Normal
- 76Cylinder #7 Injector : Current Above Normal
- 7742Secondary Throttle Position Sensor: Erratic, Intermittent, or Incorrect
- 7743Secondary Throttle Position Sensor: Voltage Above Normal
- 7744Secondary Throttle Position Sensor: Voltage Below Normal
- 7748Secondary Throttle Position Sensor: Abnormal Frequency, Pulse Width, or Period
- 79912Need Service Tool Update
- 85Cylinder #8 Injector : Current Below Normal
- 86Cylinder #8 Injector : Current Above Normal
- 912Incorrect Throttle Switch Inputs
- 913Throttle Position Sensor : Voltage Above Normal
- 914Throttle Position Sensor : Voltage Below Normal
- 918Throttle Position signal abnormal
- 943Fuel Pressure open/short to +batt
- 944Fuel Pressure short to ground
- 95Cylinder #9 Injector : Current Below Normal
- 96Cylinder #9 Injector : Current Above Normal
- E100Low Engine Oil Pressure Warning
- E17High Engine Coolant Temperature Warning
- E190Engine Overspeed Warning
- E265User Defined Shutdown
- E272Inlet Air Restriction Warning
- E360Low Engine Oil Pressure
- SPN 110 FMI 15Engine Coolant Temperature : High - Least Severe (1)
- SPN190Engine Overspeed
- SPN 190 FMI 15Engine Overspeed
- SPN 3563 FMI 3Engine Intake Manifold #1 Absolute Pressure : Voltage Above Normal
- SPN 630 FMI 2Calibration Memory : Erratic, Intermittent or Incorrect
Full CAT Engine fault code list
A generic J1939 reader pulls 1,027 of these; the other 313 need CAT Engine tooling to read in full. Every listed code is below, in code order, 100 to a page.
Codes on file
1,340
Readable as J1939 SPN/FMI
1,027
CAT Engine-specific
313
- 100-1Engine Oil Pressure : Low - most severe
- 100-17Engine Oil Pressure : Low - least severe
- 100-18Engine Oil Pressure : Low - moderate severity
- 10-2Cylinder #10 Injector : Erratic, Intermittent, or Incorrect
- 102-1Boost Pressure below normal
- 102-3Boost Pressure Sensor short to +batt
- 102-4Boost Pressure Sensor short to ground
- 10-7Cylinder #10 Injector : Not Responding Properly
- 1090-5Particulate Trap Lamp Command : Current Below Normal
- 1090-6Particulate Trap Lamp Command : Current Above Normal
- 1091-5Exhaust System High Temperature Lamp Command : Current Below Normal
- 1091-6Exhaust System High Temperature Lamp Command : Current Above Normal
- 11-2Cylinder #11 Injector : Erratic, Intermittent, or Incorrect
- 11-7Cylinder #11 Injector : Not Responding Properly
- 1194-9MIDS Main Module not communicating on link
- 12-2Cylinder #12 Injector : Erratic, Intermittent, or Incorrect
- 1237-31Engine Shutdown Overridden
- 1266-5Diagnostic Lamp Current Below Normal
- 1266-6Diagnostic Lamp Current Above Normal
- 12-7Cylinder #12 Injector : Not Responding Properly
- 1273-14Chassis Control Module : Special Instruction
- 1273-9Unable to Communicate with Chassis Control Module
- 13-2Cylinder #13 Injector : Erratic, Intermittent, or Incorrect
- 133High Intake Manifold Air Temperature - Warning
- 13-5Cylinder #13 Injector : Current Below Normal
- 13-6Cylinder #13 Injector : Current Above Normal
- 13-7Cylinder #13 Injector : Not Responding Properly
- 141Engine Overspeed
- 14-2Cylinder #14 Injector : Erratic, Intermittent, or Incorrect
- 14-5Cylinder #14 Injector : Current Below Normal
- 14-6Cylinder #14 Injector : Current Above Normal
- 14-7Cylinder #14 Injector : Not Responding Properly
- 1491-3Right Turbo Turbine Inlet Temperature Sensor : Voltage Above Normal
- 1491-4Right Turbo Turbine Inlet Temperature Sensor : Voltage Below Normal
- 1491-8Right Turbo Turbine Inlet Temperature Sensor : Abnormal Frequency, Pulse Width, or Period
- 1492-3Left Turbo Turbine Inlet Temperature Sensor : Voltage Above Normal
- 1492-4Left Turbo Turbine Inlet Temperature Sensor : Voltage Below Normal
- 1492-8Left Turbo Turbine Inlet Temperature Sensor : Abnormal Frequency, Pulse Width, or Period
- 1495-2Injector Trim Codes Not Programmed
- 151High Air Filter Restriction
- 15-2Cylinder #15 Injector : Erratic, Intermittent, or Incorrect
- 15-5Cylinder #15 Injector : Current Below Normal
- 1551-13Engine Demand Fan System : Calibration Required
- 15-6Cylinder #15 Injector : Current Above Normal
- 1577-3L Track Accumulator Pres Sensor open/short to +bat
- 1577-4Left Track Accumulator Pres Sensor short to ground
- 1578-3R Track Accumulator Pres Sensor open/short to + bat
- 1578-4R Track Accumulator Pres Sensor short to ground
- 1582-3Trans Lube Oil Temp Sensor Open/Short to +Batt
- 1582-4Trans Lube Oil Temp Sensor Short to Ground
- 1586-5Retarder Indicator Lamp open circuit
- 1586-6Retarder Indicator Lamp short to ground
- 159High Fuel Rail Pressure
- 1599-5Engine Fan Pull Solenoid Open Circuit
- 1599-6Engine Fan Pull Solenoid Short to Ground
- 1600-5Engine Fan Push Solenoid Open Circuit
- 1600-6Engine Fan Push Solenoid Short to Ground
- 1603-14Machine Control Module : Special Instruction
- 1603-9Machine Control Module not communicating on link
- 16-2Cylinder #16 Injector : Erratic, Intermittent, or Incorrect
- 1634-2Accelerator Pedal #1 Low Idle Switch : Erratic, Intermittent, or Incorrect
- 1635-2Accelerator Pedal #2 Low Idle Switch : Erratic, Intermittent, or Incorrect
- 164Injector Actuation Pressure Sensor High - Most Severe
- 164-0High Injector Actuation Pressure
- 164-2Injector Actuation Pressure Signal Erratic
- 16-5Cylinder #16 Injector : Current Below Normal
- 16-6Cylinder #16 Injector : Current Above Normal
- 16-7Cylinder #16 Injector : Not Responding Properly
- 1681-5Lighting Shutdown Timer Relay open circuit
- 1681-6Lighting Shutdown Timer Relay short to ground
- 1682-2Idle Shutdown Timer Switch loss of signal
- 1682-7Idle Shutdown Timer Switch improper response
- 168-3Battery Potential / Power Input #1 : Voltage Above Normal
- 1684-12Fuel Injection Pump : Failure
- 169Low Engine Coolant Level
- 171-3Ambient Air Temperature Sensor : Voltage Above Normal
- 171-4Ambient Air Temperature Sensor : Voltage Below Normal
- 1715-3Engine Oil Temperature Sensor #2 short to +batt
- 1715-4Engine Oil Temperature Sensor #2 short to ground
- 171-8Ambient Air Temperature Sensor : Abnormal Frequency, Pulse Width, or Period
- 1743-2Engine Operation Mode Selector Switch : Erratic, Intermittent, or Incorrect
- 1779-5Fuel Rail #1 Pressure Valve Solenoid : Current Below Normal
- 1779-6Fuel Rail #1 Pressure Valve Solenoid : Current Above Normal
- 1780-5Fuel Rail #2 Pressure Valve Solenoid : Current Below Normal
- 1780-6Fuel Rail #2 Pressure Valve Solenoid : Current Above Normal
- 1795-10Turbo #2 Outlet Pressure Sensor abnormal rate of change
- 1795-3Turbo #2 Outlet Pressure Sensor voltage above normal
- 1795-4Turbo #2 Outlet Pressure Sensor voltage below normal
- 1796-3Intake Manifold #2 Air Temperature Sensor : Voltage Above Normal
- 1796-4Intake Manifold #2 Air Temperature Sensor : Voltage Below Normal
- 1797-12Fuel Rail Pressure Sensor : Failure
- 1797-7Fuel Rail Pressure Sensor : Not Responding Properly.
- 18-14Fuel Control Valve : Special Instruction
- 1835-3Auxiliary Pressure Sensor : Voltage Above Normal
- 1835-4Auxiliary Pressure Sensor : Voltage Below Normal
- 1836-3Auxiliary Temperature Sensor : Voltage Above Normal
- 1836-4Auxiliary Temperature Sensor : Voltage Below Normal
- 1836-8Auxiliary Temperature Sensor Signal Abnormal
- 18-5Engine Fuel Injection Pump Fuel Control Valve : Current Below Normal
- 1850-3Tandem Engine Coupling Oil Pressure Sensor High/Open Circuit
Other Caterpillar machine types
Fault code lists by brand
- Volvo6,446 codes
- New Holland Tractor3,475 codes
- FPT3,033 codes
- Case IH2,992 codes
- Bobcat2,653 codes
- Challenger Tractor2,434 codes
- New Holland Combine2,274 codes
- John Deere Tractors1,884 codes
- Case Wheel Loader1,860 codes
- John Deere Engines1,853 codes
- Cummins1,847 codes
- Challenger Rubber Track Tractor1,747 codes
- Volvo Wheel Loader1,726 codes
- Deutz1,684 codes
Safety-critical: confirm before use
Safety first: park on level ground, stop the engine, and secure the machine before any inspection. Thresholds, component locations, wire numbers, fuse locations, and reset procedures can vary by model, configuration, and serial number. Confirm them in the service documentation for your exact machine.