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CAT Fault Codes List: 4043 to 4409

Page 31 of 83 of the full CAT fault code list (8,286 codes). Each entry is the code as the machine reports it and what the manufacturer data says it means.

CAT codes 4043 to 4409

  • 4043Transfer case front actuator fault
  • 4044Transfer case high range actuator fault
  • 4045Transfer case low range actuator fault
  • 4046Transfer case neutral actuator fault
  • 4047Transfer case PTO actuator fault
  • 4049Transfer case rear actuator fault
  • 40-5Auxiliary Output #2 : Current Below Normal
  • 40-6Auxiliary Output #2 : Current Above Normal
  • 407Ignition Transformer Secondary #7
  • 4076ECT2 signal does not agree with other sensors (Cold soak)
  • 4077AFTFP2 Sensor plausibility error
  • 408Ignition Transformer Secondary #8
  • 4082Fuel pump primer control issue
  • 409Ignition Transformer Secondary #9
  • 41Vehicle Overspeed Warning
  • 410Ignition Transformer Secondary #10
  • 41-038 Volt Supply Above Normal
  • 41-048 Volt Supply Below Normal
  • 4-11Cylinder #4 Injector current fault
  • 412EGRT signal does not agree with other sensors
  • 41-3ECU 8 Volts DC Supply : Voltage Above Normal
  • 41-4ECU 8 Volts DC Supply : Voltage Below Normal
  • 415Ignition Transformer Secondary #15
  • 416Ignition Transformer Secondary #16
  • 417Solenoid Return Interrupt Relay
  • 418Primary Steering Flow Lamp/Relay
  • 419Cylinder #19 Detonation
  • 4192WIF signal Out of Range HIGH
  • 4193Coolant pump outlet temperature issue
  • 4194Coolant thermostat opening issue
  • 4195Coolant thermostat mode issue
  • 420Secondary Steering Relay
  • 4209Engine Crank Without Pre-lube
  • 421Cylinder #1 Detonation Shutdown
  • 4213Engine Crank Without Fuel Injection
  • 4215Ground-Level Shutdown Activated
  • 4216Transmission Reverse Solenoid Valve 3 Voltage Above Normal 3
  • 42173 Voltage Above Normal 3
  • 4218Transmission Shift Rail 1 Position 3 Voltage Above Normal 2
  • 4219Transmission Shift Rail 2 Position 3 Voltage Above Normal 2
  • 422Cylinder #2 Detonation Shutdown
  • 4220Transmission Shift Rail 3 Position 3 Voltage Above Normal 2
  • 422114 Special Instruction 3
  • 4227CC Oil Separator Speed: Not spinning
  • 423Front Brake Accumulator Pressure Switch
  • 424Rear Brake Accumulator Pressure Switch
  • 4244Engine Run Relay
  • 4256Cranking Voltage
  • 427Front Axle Oil Temperature Sensor
  • 428Rear Axle Oil Temperature Sensor
  • 429Steering Pump Oil Pressure Sensor
  • 43Low System Voltage Warning
  • 430Engine Starter Solenoid Voltage
  • 43-02Key Switch Fault
  • 431Cylinder #11 Detonation Shutdown
  • 43-2Battery Potential (Voltage) Switched : Erratic, Intermittent, or Incorrect
  • 433Hydraulic Oil Filter Differential Pressure Switch
  • 434Hydraulic Pilot Oil Pressure Sensor
  • 4341Aftertreatment DEF Line Heater 1 Preliminary FMI
  • 4342Aftertreatment DEF Line Heater 2 State
  • 4343Aftertreatment DEF Line Heater 2 Preliminary FMI
  • 4344Aftertreatment DEF Line Heater 3 State
  • 4345Aftertreatment DEF Line Heater 3 Preliminary FMI
  • 4346Aftertreatment DEF Line Heater 4 State
  • 4347Aftertreatment DEF Line Heater 4 Preliminary FMI
  • 435Cylinder #15 Detonation Shutdown
  • 4352Aftertreatment DEF Doser Fault Suppression Request
  • 4353Aftertreatment DEF Doser Heating Mode Request
  • 4358Aftertreatment SCR Catalyst Exhaust Gas Differential Pressure
  • 436Torque Converter Oil Pressure Sensor
  • 4360Aftertreatment SCR Catalyst Intake Gas Temperature
  • 4363Aftertreatment SCR Catalyst Outlet Gas Temperature
  • 4364Aftertreatment SCR Catalyst Conversion Efficiency
  • 437Powertrain Filter Pressure Switch
  • 4374Aftertreatment DEF Pump Motor Speed
  • 4375Aftertreatment DEF Pump Drive Percentage
  • 4376Aftertreatment DEF Return Valve
  • 438Hydraulic Control Valve Warm Up Solenoid #1
  • 4384Aftertreatment DEF Actual Dosing Quantity
  • 4386Aftertreatment DEF Actual Quantity of Integrator
  • 4387Aftertreatment DEF Dosing Absolute Pressure
  • 439Hydraulic Control Valve Warm Up Solenoid #2
  • 4390Aftertreatment DEF Dosing Temperature
  • 4393Aftertreatment DEF Line Heater 1 State
  • 4394Aftertreatment DEF Line Heater 1 Preliminary FMI
  • 4395Aftertreatment DEF Line Heater 2 State
  • 4396Aftertreatment DEF Line Heater 2 Preliminary FMI
  • 4397Aftertreatment DEF Line Heater 3 State
  • 4398Aftertreatment 2 DEF Line Heater 3 Fault
  • 4399Aftertreatment 2 DEF Line Heater 4 State Fault
  • 44Secondary Fuel Level voltage high
  • 440Hydraulic Control Valve Warm Up Solenoid #3
  • 4400Aftertreatment 2 DEF Line Heater 4 Fault
  • 4401Aftertreatment 2 DEF Dosing Quantity Fault
  • 4403Aftertreatment 2 DEF Integrator Quantity Fault
  • 4405Aftertreatment 2 DEF Doser Fault Suppression
  • 4406Aftertreatment 2 DEF Doser Heating Mode Fault
  • 4407Aftertreatment 2 DEF Line Heater 1 Fault
  • 4408Aftertreatment 2 DEF Line Heater 2 Fault
  • 4409Aftertreatment 2 DEF Line Heater 3 Fault
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