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Komatsu Engines Fault Codes List: 6264 to AB

Page 9 of 11 of the full Komatsu Engines fault code list (1,067 codes). Each entry is the code as the machine reports it and what the manufacturer data says it means.

Komatsu Engines codes 6264 to AB

  • 6264Fan Control Circuit - Voltage Below Normal or Shorted to Low Source
  • 6265Aftertreatment 1 Diesel Particulate Filter System - Mechanical System Not Responding or Out of Adjustment
  • 629Turbocharger 1 Compressor Inlet Pressure - Data Valid But Below Normal Operating Range - Moderately Severe Level
  • 6336Crankcase Breather Filter Heater Circuit - Voltage Above Normal or Shorted to High Source
  • 6337Crankcase Breather Filter Heater Circuit - Voltage Below Normal or Shorted to Low Source
  • 6416Aftertreatment Regeneration Inhibited Due to Inhibit Switch - Condition Exists
  • 6417SAE J1939 Multiplexing Remote Accelerator Pedal or Lever Sensor System - Received Network Data in Error
  • 6418Engine Brake Actuator Driver 1 Circuit - Voltage Above Normal or Shorted to High Source
  • 6419Engine Brake Actuator Driver 1 Circuit - Voltage Below Normal or Shorted to Low Source
  • 6421Engine Brake Actuator Driver Output 2 Circuit - Voltage Above Normal or Shorted to High Source
  • 6422Engine Brake Actuator Driver Output 2 Circuit - Voltage Below Normal or Shorted to Low Source
  • 6456Engine Fan Clutch 2 Control Circuit - Voltage Above Normal or Shorted to High Source
  • 6457Engine Fan Clutch 2 Control Circuit - Voltage Below Normal or Shorted to Low Source
  • 6458Aftertreatment 1 Intake NOx Sensor - Data Not Rational - Drifted High
  • 6459Aftertreatment 1 Intake NOx Sensor - Data Not Rational - Drifted Low
  • 6462Aftertreatment 1 Outlet NOx Sensor - Data Not Rational - Drifted High
  • 6463Aftertreatment 1 Outlet NOx Sensor - Data Not Rational - Drifted Low
  • 6464Aftertreatment 1 Outlet NOx - Data Erratic, Intermittent, or Incorrect
  • 6467Fan Speed - Data Valid But Above Normal Operating Range - Least Severe Level
  • 6468Fan Speed - Data Valid But Below Normal Operating Range - Least Severe Level
  • 6469Fan Speed - Data Erratic, Intermittent, or Incorrect
  • 6471Engine Fan Blade Pitch Position Sensor Circuit - Voltage Above Normal or Shorted to High Source
  • 6472Engine Fan Blade Pitch Position Sensor Circuit - Voltage Below Normal or Shorted to Low Source
  • 6473Engine Fan Blade Pitch - Data Erratic, Intermittent, or Incorrect
  • 6475Aftertreatment 1 Diesel Exhaust Fluid Tank Heater - Mechanical System Not Responding or Out of Adjustment
  • 6476Aftertreatment 1 Diesel Exhaust Fluid Tank Heater - Data Valid But Below Normal Operating Range - Moderately Severe Level
  • 6477Aftertreatment Diesel Exhaust Fluid Line Heater Relay Circuit - Voltage Above Normal or Shorted to High Source
  • 6478Aftertreatment Diesel Exhaust Fluid Line Heater Relay Circuit - Voltage Below Normal or Shorted to Low Source
  • 6479Aftertreatment 1 Diesel Exhaust Fluid Tank Heater Circuit - Voltage Above Normal or Shorted to High Source
  • 6481Aftertreatment 1 Diesel Exhaust Fluid Tank Heater Circuit - Voltage Below Normal or Shorted to Low Source
  • 6482Aftertreatment 1 Diesel Exhaust Fluid Line Heater 1 Circuit - Current Below Normal or Open Circuit
  • 6483Aftertreatment 1 Diesel Exhaust Fluid Line Heater 2 Circuit - Current Below Normal or Open Circuit
  • 6484Aftertreatment 1 Diesel Exhaust Fluid Line Heater 3 Circuit - Current Below Normal or Open Circuit
  • 649Change Lubricating Oil and Filter - Condition Exists
  • 6499ECU Power Output Supply Voltage 1 - Data Valid But Below Normal Operating Range - Least Severe Level
  • 6511Maintain ECU Power Lamp Circuit - Voltage Above Normal or Shorted to High Source
  • 6513Aftertreatment 1 Diesel Exhaust Fluid Dosing Unit 1 Heater - Data Valid But Below Normal Operating Range - Least Severe Level
  • 6517Aftertreatment SCR Catalyst Conversion Efficiency - Data Valid But Below Normal Operating Range - Least Severe Level
  • 6521Aftertreatment 1 Outlet NOx Sensor Circuit - Voltage Below Normal or Shorted to Low Source
  • 6522 (2-Wire Sensor)Coolant Level Sensor 1 Circuit - Voltage Above Normal or Shorted to High Source
  • 6523 (2-Wire Sensor)Coolant Level Sensor 1 Circuit - Voltage Below Normal or Shorted to Low Source
  • 6523 (3-Wire Sensor)Coolant Level Sensor 1 Circuit - Voltage Below Normal or Shorted to Low Source
  • 6524Engine Oil Temperature Sensor 1 Circuit - Voltage Above Normal or Shorted to High Source
  • 6525Engine Oil Temperature Sensor 1 Circuit - Voltage Below Normal or Shorted to Low Source
  • 6527Aftertreatment Diesel Exhaust Fluid Return Valve - Mechanical System Not Responding or Out of Adjustment
  • 6529Aftertreatment 1 Diesel Exhaust Fluid Dosing Unit Heater Relay Circuit - Voltage Above Normal or Shorted to High Source
  • 6531Aftertreatment 1 Diesel Exhaust Fluid Line Heater 1 Circuit - Voltage Above Normal or Shorted to High Source
  • 6532Aftertreatment 1 Diesel Exhaust Fluid Line Heater 1 Circuit - Voltage Below Normal or Shorted to Low Source
  • 6533Aftertreatment 1 Diesel Exhaust Fluid Line Heater 2 Circuit - Voltage Above Normal or Shorted to High Source
  • 6534Aftertreatment 1 Diesel Exhaust Fluid Line Heater 2 Circuit - Voltage Below Normal or Shorted to Low Source
  • 6535Aftertreatment 1 Diesel Exhaust Fluid Line Heater 3 Circuit - Voltage Above Normal or Shorted to High Source
  • 6536Aftertreatment 1 Diesel Exhaust Fluid Line Heater 3 Circuit - Voltage Below Normal or Shorted to Low Source
  • 6539Aftertreatment 1 Diesel Oxidation Catalyst Intake Temperature - Data Erratic, Intermittent, or Incorrect
  • 6551Aftertreatment 1 Diesel Particulate Filter Outlet Pressure Sensor Circuit - Voltage Above Normal or Shorted to High Source
  • 6552Aftertreatment 1 Diesel Particulate Filter Outlet Pressure Sensor Circuit - Voltage Below Normal or Shorted to Low Source
  • 6553Aftertreatment 1 Diesel Particulate Filter Outlet Pressure - Data Erratic, Intermittent, or Incorrect
  • 6559Aftertreatment 1 Diesel Exhaust Fluid Tank Temperature Sensor Circuit - Voltage Below Normal or Shorted to Low Source
  • 6563PTO Governor State - Data Erratic, Intermittent, or Incorrect
  • 6565Aftertreatment 1 Outlet NOx Sensor - Abnormal Rate of Change
  • 6568Aftertreatment Regeneration Inhibit Switch - Data Erratic, Intermittent, or Incorrect
  • 6569Aftertreatment 1 SCR Outlet Temperature Sensor Circuit - Voltage Above Normal or Shorted to High Source
  • 6571Aftertreatment 1 SCR Outlet Temperature Sensor Circuit - Voltage Below Normal or Shorted to Low Source
  • 6581Aftertreatment 1 Outlet NOx Sensor Heater - Abnormal Rate of Change
  • 6582Aftertreatment 1 Outlet NOx Sensor Power Supply - Data Erratic, Intermittent, or Incorrect
  • 6583Auxiliary Temperature Sensor Input 1 - Special Instructions
  • 6584Auxiliary Pressure Sensor Input 2 - Special Instructions
  • 6595Engine Speed - Root Cause Not Known
  • 6596Diesel Particulate Filter Active Regeneration Inhibited Due to System Timeout - Condition Exists
  • 6725Intake Manifold 1 Pressure- Data Valid But Above Normal Operating Range - Least Severe Level
  • 6725 (Heavy Duty)Intake Manifold 1 Pressure- Data Valid But Above Normal Operating Range - Least Severe Level
  • 686Turbocharger 1 Speed - Data Erratic, Intermittent, or Incorrect
  • 687Turbocharger 1 Speed - Data Valid But Below Normal Operating Range - Moderately Severe Level
  • 687 (B)Turbocharger Speed Sensor - Below Normal Operating Range
  • 687 (CL)Turbocharger Number 1 Speed Low - Data Valid but Below Normal Operational Range - Moderately Severe Level
  • 688Engine Oil Level — Data Valid But Above Normal Operational Range — Most Severe Level
  • 689Engine Crankshaft Speed/Position - Data Erratic, Intermittent, or Incorrect
  • 691Turbocharger #1 Compressor Inlet Temperature Sensor Circuit - Voltage Above Normal or Shorted to High Source
  • 692Turbocharger Number 1 Compressor Inlet Temperature Sensor Circuit - Voltage Below Normal or Shorted to Low Source
  • 693Turbocharger 1 Compressor Intake Temperature - Data Erratic, Intermittent, or Incorrect
  • 697Engine ECU Temperature Sensor Circuit - Voltage Above Normal, or Shorted to High Source
  • 698Engine ECU Temperature Sensor Circuit - Voltage Below Normal, or Shorted to Low Source
  • 699Engine ECU Temperature - Data Erratic, Intermittent, or Incorrect
  • 731Engine Speed/Position Camshaft and Crankshaft Misalignment - Mechanical System Not Responding or Out of Adjustment
  • 731 (B)Engine Speed Sensor/Position Camshaft and Crankshaft Misalignment - Mechanical System Not Responding Properly or Out of Adjustment
  • 731 (BM)Engine Speed Sensor/Position Camshaft and Crankshaft Misalignment - Mechanical System Not Responding Properly or Out of Adjustment
  • 741Turbocharger 1 Compressor Intake Pressure Circuit - Voltage Above Normal or Shorted to High Source
  • 742Turbocharger 1 Compressor Intake Pressure Circuit - Voltage Below Normal or Shorted to Low Source
  • 743Turbocharger 1 Compressor Intake Pressure - Data Erratic, Intermittent, or Incorrect
  • 757Electronic Control Module Data Lost - Condition Exists
  • 769Brake Switch Circuit - Voltage Above Normal or Shorted to High Source
  • 778Engine Camshaft Speed / Position Sensor - Data Erratic, Intermittent, or Incorrect
  • 779Auxiliary Equipment Sensor Input #3 (OEM Switch) - Root Cause Not Known
  • 784Adaptive Cruise Control Mode - Data Erratic, Intermittent, or Incorrect
  • 951Cylinder Power Imbalance Detected
  • 957EGR Valve Position - Data Erratic, Intermittent, or Incorrect
  • 958VGT Position Sensor - Data Erratic, Intermittent, or Incorrect
  • A8Rated Speed Adjustment Volume (Isochronous) High Error
  • A9Rated Speed Adjustment Volume (Isochronous) Low Error
  • AARated Speed Adjustment Volume (Droop) High Error
  • ABRated Speed Adjustment Volume (Droop) Low Error
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