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CAT Fault Codes List & Code Lookup

Look up 8,255 CAT fault codes and error codes, in plain English. 43 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 fault code guides

Full CAT fault code list

A generic J1939 reader pulls 564 of these; the other 7,691 need CAT tooling to read in full. Every listed code is below, in code order, 100 to a page.

Codes on file

8,255

Readable as J1939 SPN/FMI

564

CAT-specific

7,691

  • 0001-11Cylinder #1 Injector
  • 0002-11Cylinder #2 Injector
  • 0003-11Cylinder #3 Injector
  • 0004-11Cylinder #4 Injector
  • 0005-11Cylinder #5 Injector
  • 0006-11Cylinder #6 Injector
  • 0022-11Primary to Secondary
  • 0022-13Engine Speed Signal Calibration Not 0171-03 Ambient Air Temperature voltage high.. 146
  • 0030-08PTO Throttle signal
  • 0041-038 Volt Supply voltage
  • 0041-048 Volt Supply voltage
  • 0043-02Key Switch Fault (71)
  • 0052-11Air Inlet Shutoff
  • 0054-05Auxiliary Output #06
  • 0054-06Auxiliary Output #06
  • 0055-05Auxiliary Output #07
  • 0064-12Secondary Engine
  • 0071-00Idle Shutdown
  • 0071-01Idle Shutdown (47) programmed to at least three minutes.
  • 0071-14PTO Shutdown (47)
  • 0084-01Vehicle Speed loss of
  • 0084-02Vehicle Speed signal
  • 0084-08Vehicle Speed signal
  • 0084-10Vehicle Speed signal
  • 0091-08Throttle Position The ECM sets "Throttle Position" to 0%. "DIAG" will
  • 0091-13Throttle Position out
  • 0100-01Low Oil Pressure
  • 0100-03Oil Pressure voltage
  • 0100-04Oil Pressure voltage
  • 0100-11Very Low Oil Pressure
  • 0102-00Excessive Boost
  • 0102-03Boost Pressure
  • 0102-04Boost Pressure "DIAG" will be displayed next to the status for
  • 0105-00High Intake Manifold
  • 0105-03Intake Manifold Air Temperature voltage ATA (SAE J1587 / J1708) Data Link Circuit -
  • 0105-04Intake Manifold Air
  • 0105-11Very High Intake Manifold Air Temperature
  • 0108-03Barometric Pressure voltage high (26).. 139
  • 0108-04Barometric Pressure
  • 0110-00High Coolant
  • 0110-03Coolant Temperature
  • 0110-04Coolant Temperature
  • 0110-11Very High Coolant
  • 0111-01Low Coolant Level
  • 0111-02Coolant Level signal
  • 0111-03Coolant Level voltage
  • 0111-04Coolant Level voltage
  • 0111-11Very Low Coolant
  • 0121-05Low/High Retarder
  • 0121-06Low/High Retarder
  • 0122-05MedlHigh Retarder
  • 0122-06Med/High Retarder
  • 0168-02ECM Battery Power 0171-03 Ambient Air
  • 0171-04Ambient Air
  • 0171-11Ambient Air
  • 0174-00High Fuel Temperature
  • 0174-03Fuel Temperature
  • 0174-04Fuel Temperature
  • 0190-00Engine Overspeed
  • 0191-07Transmission Not
  • 02Event Recorder Data Lost
  • 0224-11Theft Deterrent Active
  • 0224-14Theft Deterrent Active
  • 0231-02J1939 Data Incorrect
  • 0231-11J1939 Data Link Fault
  • 0231-12J1939 Device Not
  • 0232-035 Volt Supply voltage
  • 0232-045 Volt Supply voltage
  • 0246-11Brake Pedal Switch #1
  • 0247-11Brake Pedal Switch #2
  • 0249-11J1922 Data Link Fault
  • 0252-11Engine Software
  • 0253-02Check Customer or
  • 0253-11Check Transmission
  • 03"Voltage above normal"
  • 04"Voltage below normal"
  • 05"Current below normal"
  • 06"Current above normal"
  • 07"Mechanical system not responding properly"
  • 08"Abnormal frequency, pulse width, or period"
  • 09"Abnormal update rate"
  • 10If the problem seems to occur during the rain or a washing, thoroughly inspect the connectors for moisture. Refer to
  • 100Engine oil pressure below dealer programmed engine RPM value
  • 1000to 1200 rpm range in order to perform a timing
  • 100-01Low Oil Pressure Warning
  • 100-03Oil Pressure voltage high
  • 100-04Oil Pressure voltage low
  • 100-1Engine Oil Pressure : Low - Least Severe (1)
  • 100-10Engine Oil Pressure : Abnormal Rate of Change
  • 100-11Engine Oil Pressure : Low - Most Severe (3)
  • 1002Alternator Actuation Enable Relay
  • 100-3Engine Oil Pressure : Voltage Above Normal
  • 100-4Engine Oil Pressure : Voltage Below Normal
  • 1005Boom Swing Position Sensor
  • 1006Steering Wheel Stowed Switch
  • 1007Joystick Mapping Switch
  • 1008Rear Facing Position Seat Switch
  • 1009Front Facing Position Seat Switch
  • 101Engine crankcase pressure issue.
  • 101-0Engine Crankcase Pressure : High - Least Severe (1)

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