Diagnostics
Komatsu Engines Fault Codes List & Code Lookup
Look up 1,067 Komatsu Engines fault codes and error codes, in plain English. 3 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.
Komatsu Engines fault code guides
Full Komatsu Engines fault code list
A generic J1939 reader pulls 893 of these; the other 174 need Komatsu Engines tooling to read in full. Every listed code is below, in code order, 100 to a page.
Codes on file
1,067
Readable as J1939 SPN/FMI
893
Komatsu Engines-specific
174
- 1Exhaust Gas Pressure Sensor Number 1 Circuit - Voltage Above Normal, or Shorted to High Source
- 111Engine Control Module Critical Internal Failure - Bad Intelligent Device or Component
- 1117Power Supply Lost With Ignition On - Data Erratic, Intermittent, or Incorrect
- 1117 (AUTO)Power Lost Without Ignition Off - Data Erratic, Intermittent, or Incorrect
- 1117 (MAR)Power Lost without Ignition Off - Data Erratic, Intermittent, or Incorrect
- 1119Engine Coolant Temperature - Data Valid But Above Normal Operating Range - Moderately Severe Level
- 1139Injector Solenoid Driver Cylinder 1 - Mechanical System Not Responding Properly or Out of Adjustment
- 1141Injector Solenoid Driver Cylinder 2 - Mechanical System Not Responding Properly or Out of Adjustment
- 1142Injector Solenoid Driver Cylinder 3 - Mechanical System Not Responding Properly or Out of Adjustment
- 1143Injector Solenoid Driver Cylinder 4 - Mechanical System Not Responding Properly or Out of Adjustment
- 1144Injector Solenoid Driver Cylinder 5 - Mechanical System Not Responding Properly or Out of Adjustment
- 1145Injector Solenoid Driver Cylinder 6 - Mechanical System Not Responding Properly or Out of Adjustment
- 115Engine Magnetic Crankshaft Speed/Position Lost Both of Two Signals - Data Erratic, Intermittent, or Incorrect
- 122Intake Manifold 1 Pressure Sensor Circuit - Voltage Above Normal or Shorted to High Source
- 1228EGR Valve Position - Data Erratic, Intermittent, or, Incorrect
- 1229VGT Position Sensor - Data Erratic, Intermittent, or Incorrect
- 123Intake Manifold 1 Pressure Sensor Circuit - Voltage Below Normal or Shorted to Low Source
- 1239Accelerator Pedal or Lever Position Sensor 2 Circuit - Voltage Above Normal or Shorted to High Source
- 124Intake Manifold 1 Pressure - Data Valid But Above Normal Operating Range - Moderately Severe Level
- 1241Accelerator Pedal or Lever Position Sensor 2 Circuit - Voltage Below Normal or Shorted to Low Source
- 1242Accelerator Pedal or Lever Position Sensor Number 1 and Number 2 - Data Erratic, Intermittent, or Incorrect
- 125Intake Manifold 1 Pressure - Data Valid But Below Normal Operating Range - Moderately Severe Level
- 131Accelerator Pedal or Lever Position Sensor 1 Circuit - Voltage Above Normal or Shorted to High Source
- 132Accelerator Pedal or Lever Position Sensor 1 Circuit - Voltage Below Normal or Shorted to Low Source
- 133Remote Accelerator Pedal or Lever Position Sensor 1 Circuit - Voltage Above Normal, or shorted to High Source
- 134Remote Accelerator Pedal or Lever Position Sensor 1 Circuit - Voltage Below Normal, or Shorted to Low Source
- 135Engine Oil Rifle Pressure 1 Sensor Circuit - Voltage Above Normal or Shorted to High Source
- 1357Engine Oil Level Remote Reservoir - Data Valid but Below Normal Operational Range - Moderately Severe Level
- 1358Accelerator Pedal or Lever Position Sensor 1 Circuit - Voltage Above Normal or Shorted to High Source
- 1359Accelerator Pedal or Lever Position Sensor 1 Circuit - Voltage Below Normal or Shorted to Low Source
- 135 (AUTO)Oil Pressure Sensor Circuit - Voltage Above Normal, or Shorted to High Source
- 135 (MAR)Oil Pressure Sensor Circuit - Voltage Above Normal, or Shorted to High Source
- 1361Remote Accelerator Pedal or Lever Position Sensor 1 Circuit - Voltage Below Normal or Shorted to Low Source
- 1363Intake Manifold 1 Pressure - Data Valid but Below Normal Operational Range - Least Severe Level
- 1367Engine Camshaft Speed-Position Sensor - Data Erratic, Intermittent, or Incorrect
- 1369Auxiliary Temperature Sensor Input 1 Circuit - Voltage Above Normal, or Shorted to High Source
- 1371Auxiliary Pressure Sensor Input 1 Circuit - Voltage Above Normal, or Shorted to High Source
- 1372Auxiliary Pressure Sensor Input 1 Circuit - Voltage Below Normal, or Shorted to Low Source
- 1373Start Enable Device 1 Circuit (Ether Injection) - Root Cause Not Known
- 1381Auxiliary Temperature Sensor Input 1 - Special Instructions
- 1385Accelerator Pedal or Lever Position Sensor 1 Circuit - Voltage Above Normal or Shorted to High Source
- 1387Engine Commanded Shutdown - Condition Exists
- 141Engine Oil Rifle Pressure 1 Sensor Circuit - Voltage Below Normal or Shorted to Low Source
- 1411Generator Output Frequency Adjust Potentiometer Circuit - Voltage Above Normal or Shorted to High Source
- 1412Droop Adjust Potentiometer Circuit - Voltage Above Normal or Shorted to High Source
- 1418Gain Adjust Potentiometer Circuit - Voltage Above Normal or Shorted to High Source
- 141 (AUTO)Oil Pressure Sensor Circuit - Voltage Below Normal, or Shorted to Low Source
- 141 (MAR)Oil Pressure Sensor Circuit - Voltage Below Normal or Shorted to Low Source
- 1427Overspeed Shutdown Relay Driver Diagnostic has detected an Error - Condition Exists
- 1428Low Oil Pressure (LOP) Shutdown Relay Driver Diagnostic has Detected an Error - Condition Exists
- 1429High Engine Temperature (HET) Shutdown Relay Driver Diagnostic Has Detected an Error - Condition Exists
- 143Engine Oil Rifle Pressure - Data Valid But Below Normal Operational Range - Moderately Severe Level
- 143 (B)Engine Oil Rifle Pressure - Data Valid but Below Normal Operational Range - Moderately Severe Level
- 143 (BM)Engine Oil Rifle Pressure - Data Valid but Below Normal Operational Range - Moderately Severe Level
- 144Engine Coolant Temperature 1 Sensor Circuit - Voltage Above Normal or Shorted to High Source
- 144 (B)Engine Coolant Temperature 1 Sensor Circuit - Voltage Above Normal or Shorted to High Source
- 144 (BM)Engine Coolant Temperature 1 Sensor Circuit - Voltage Above Normal or Shorted to High Source
- 145Engine Coolant Temperature 1 Sensor Circuit - Voltage Below Normal or Shorted to Low Source
- 145 (B)Engine Coolant Temperature 1 Sensor Circuit - Voltage Below Normal or Shorted to Low Source
- 145 (BM)Engine Coolant Temperature 1 Sensor Circuit - Voltage Below Normal or Shorted to Low Source
- 146Engine Coolant Temperature - Data Valid But Above Normal Operational Range - Moderately Severe Level
- 146 (B)Engine Coolant Temperature - Data Valid but Above Normal Operational Range - Moderately Severe Level
- 146 (BM)Engine Coolant Temperature - Data Valid but Above Normal Operational Range - Moderately Severe Level
- 147Accelerator Pedal or Lever Position 1 Sensor Circuit Frequency - Data Valid but Below Normal Operational Range - Most Severe Level
- 148Accelerator Pedal or Lever Position Sensor 1 - Data Valid but Above Normal Operational Range - Most Severe Level
- 151Engine Coolant Temperature - Data Valid But Above Normal Operating Range - Most Severe Level
- 1514Accelerator Pedal or Lever Position Sensor 1 Circuit Frequency - Abnormal Frequency, Pulse Width, or Period
- 1515SAE J1939 Multiplexed Accelerator Pedal or Lever Sensor System - Received Network Data In Error
- 151 (B)Engine Coolant Temperature - Data Valid but Above Normal Operational Range - Most Severe Level
- 151 (BM)Engine Coolant Temperature - Data Valid but Above Normal Operational Range - Most Severe Level
- 153Intake Manifold Air Temperature Sensor Circuit - Voltage Above Normal or Shorted to High Source
- 1539Auxiliary Pressure Sensor Input 1 Circuit - Voltage Above Normal or Shorted to High Source
- 154Intake Manifold Air Pressure/Temperature Sensor Circuit - Voltage Below Normal or Shorted to Low Source
- 1543Auxiliary Pressure Sensor Input 1 Circuit - Voltage Below Normal or Shorted to Low Source
- 1544Auxiliary Pressure Sensor Input 1 - Special Instructions
- 155Intake Manifold 1 Temperature - Data Valid But Above Normal Operating Range - Most Severe Level
- 155 (B)Intake Manifold 1 Temperature - Data Valid But Above Normal Operating Range - Most Severe Level
- 155 (BM)Intake Manifold 1 Temperature - Data Valid but Above Normal Operational Range - Most Severe Level
- 1595Remote Accelerator Pedal or Lever Position Sensor 1 Circuit - Voltage Above Normal or Shorted to High Source
- 1596Auxiliary Temperature Sensor Input 1 Circuit - Voltage Below Normal or Shorted to Low Source
- 1597Engine Control Module Critical Internal Failure - Bad Intelligent Device or Component
- 1621Auxiliary Pressure Sensor Input 1 Circuit - Voltage Below Normal or Shorted to Low Source
- 1633Komnet Datalink Cannot Transmit - Data Erratic, Intermittent, or Incorrect
- 1639Auxiliary Equipment Sensor Input Number 3 (OEM Switch) - Root Cause Not Known
- 1654Engine Misfire Cylinder 1 - Condition Exists.
- 1655Engine Misfire Cylinder 2 - Condition Exists.
- 1656Engine Misfire Cylinder 3 - Condition Exists.
- 1657Engine Misfire Cylinder 4 - Condition Exists.
- 1658Engine Misfire Cylinder 5 - Condition Exists.
- 1659Engine Misfire Cylinder 6 - Condition Exists.
- 1663Catalyst Inlet Temperature Sensor Swapped with Outlet - Condition Exists.
- 1664Aftertreatment Diesel Oxidation Catalyst Missing - Condition Exists
- 1665Exhaust Gas Temperature 1 Circuit — Voltage Below Normal, or Shorted to Low Source.
- 1666Exhaust Gas Temperature 1 Circuit — Voltage Above Normal, or Shorted to Low Source
- 1667Exhaust Gas Temperature 1 — Data Erratic, Intermittent, or Incorrect
- 1668Catalyst Tank Level Sensor Circuit — Voltage Below Normal, or Shorted to Low Source
- 1668 (2-Wire Sensor)Aftertreatment 1 Diesel Exhaust Fluid Tank Level Sensor Circuit - Voltage Below Normal or Shorted to Low Source
- 1668 (3-Wire Sensor)Aftertreatment 1 Diesel Exhaust Fluid Tank Level Sensor Circuit - Voltage Below Normal or Shorted to Low Source
- 1669Catalyst Tank Level Sensor Circuit — Voltage Above Normal, or Shorted to High Source
- 1669 (2-Wire Sensor)Aftertreatment 1 Diesel Exhaust Fluid Tank Level Sensor Circuit - Voltage Above Normal or Shorted to High Source
Other Komatsu machine types
Fault code lists by brand
- CAT8,255 codes
- 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
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.