Caterpillar Fault Codes
This is the complete list of Caterpillar fault codes. If you are currently working on a Caterpillar engine and need more information check out our selection of factory printed CAT Service Manuals
| PID/SID | FMI | Fault | Description |
| 1 | 11 | injector solenoid cyl#1 | current below normal or open |
| 2 | 11 | injector solenoid cyl#2 | current below normal or open |
| 3 | 11 | injector solenoid cyl#3 | current below normal or open |
| 4 | 11 | injector solenoid cyl#4 | current below normal or open |
| 5 | 11 | injector solenoid cyl#5 | current below normal or open |
| 6 | 11 | injector solenoid cyl#6 | current below normal or open |
| 22 | 13 | ECU | speed signal calibration not performed |
| 30 | 8 | PTO | PTO throttle signal invalid |
| 30 | 13 | PTO | PTO throttle signal out of calibration |
| 32 | 5 | turbo wastegate solenoid | current below normal |
| 32 | 6 | turbo wastegate solenoid | current above normal or shorted to ground |
| 32 | 11 | turbo wastegate solenoid | current mismatch |
| 41 | 3 | 8 volt supply | voltage above normal or shorted high |
| 41 | 4 | 8 volt supply | voltage below normal or shorted low |
| 42 | 11 | Injection Actuation Pump | output failure |
| 43 | 2 | ECU | key switch |
| 64 | 2 | speed sensor | loss of signal |
| 64 | 11 | speed sensor | erratic data signal |
| 70 | 5 | intake heater | current beow normal |
| 70 | 6 | intake heater | current above normal or shorted to ground |
| 71 | 1 | idle | idle shutdown |
| 71 | 14 | PTO | PTO shutdown |
| 84 | 0 | vehicle speed sensor | over speed warning |
| 84 | 1 | vehicle speed sensor | loss of signal |
| 84 | 2 | vehicle speed sensor | erratic/incorrect data signal |
| 84 | 8 | vehicle speed sensor | signal out of normal range |
| 84 | 10 | vehicle speed sensor | abnornal rate of change |
| 84 | 14 | vehicle speed sensor | quick stop occurance |
| 91 | 8 | throttle position | invalid signal |
| 91 | 13 | throttle position | out of calibration |
| 94 | 1 | fuel pressure | low fuel pressure |
| 94 | 3 | fuel pressure | voltage above normal |
| 94 | 4 | fuel pressure | voltage below normal |
| 94 | 11 | fuel pressure | low cranking fuel pressure |
| 96 | 3 | fuel level | voltage above normal |
| 96 | 4 | fuel level | voltage below normal |
| 100 | 1 | oil pressure sensor | low pressure warning |
| 100 | 3 | oil pressure sensor | voltage above normal |
| 100 | 4 | oil pressure sensor | voltage below normal |
| 100 | 11 | oil pressure sensor | very low oil pressure |
| 102 | 1 | intake mfld pres sensor | low boost pressure |
| 102 | 3 | intake mfld pres sensor | voltage above normal or shorted high |
| 102 | 4 | intake mfld pres sensor | voltage below normal or open circuit |
| 102 | 2 | intake mfld pres sensor | data does not match current conditions |
| 102 | 7 | intake mfld pres sensor | not responding |
| 105 | 3 | intake mfld tem sensor | voltage above normal or shorted high |
| 105 | 4 | intake mfld tem sensor | voltage below normal or open circuit |
| 105 | 0 | intake mfld tem sensor | temperature above protection limit |
| 105 | 11 | intake mfld tem sensor | very high intake air temperature |
| 108 | 3 | barometric pres sensor | voltage above normal or shorted high |
| 108 | 4 | barometric pres sensor | voltage below normal or shorted low |
| 108 | 2 | barometric pres sensor | erratic/incorrect data signal |
| 110 | 3 | coolant temp sensor | voltage above normal or shorted high |
| 110 | 4 | coolant temp sensor | voltage below normal or open circuit |
| 110 | 0 | coolant temp sensor | temperature above normal range |
| 110 | 11 | coolant temp sensor | very high coolant temperature |
| 111 | 2 | coolant level sensor | invalid signal |
| 111 | 3 | coolant level sensor | voltage above normal or shorted high |
| 111 | 4 | coolant level sensor | voltage below normal or open circuit |
| 111 | 1 | coolant level sensor | level below normal range |
| 111 | 11 | coolant level sensor | very low coolant level |
| 128 | 3 | sec fuel level | voltage below normal or shorted low |
| 128 | 4 | sec fuel level | voltage above normal or shorted high |
| 164 | 2 | injection actuation pressure | erratic signal |
| 164 | 3 | injection actuation pressure | voltage above normal |
| 164 | 4 | injection actuation pressure | voltage below normal |
| 164 | 0 | injection actuation pressure | excessive pressure |
| 164 | 11 | injection actuation pressure | system failure |
| 168 | 2 | ECM failure | supply voltage intermittent |
| 168 | 1 | ECM failure | supply voltage low |
| 168 | 0 | ECM failure | supply voltage high |
| 173 | 0 | exhaust temperature | derate for high exhaust temperature |
| 173 | 11 | exhaust temperature | derate for very high exhaust temperature |
| 186 | 4 | PTO | PTO shutdown switch v oltage low |
| 186 | 14 | PTO | PTO shutdown switch occurance |
| 190 | 0 | engine speed | overspeed warning |
| 190 | 2 | engine speed | loos of data signal |
| 190 | 11 | engine speed | erratic signal |
| 224 | 11 | theft deterent | active signal |
| 224 | 14 | theft deterent | active signal when cranking |
| 231 | 2 | J1939 data | incorrect data fron J1939 |
| 231 | 11 | J1939 data | J1939 configuration |
| 231 | 12 | J1939 data | loss of data signal |
| 231 | 14 | J1939 data | transmission data link derate |
| 232 | 3 | 5 volt supply | voltage above normal |
| 232 | 4 | 5 volt supply | voltage below normal |
| 232 | 3 | sensor supply | voltage above normal or shorted high |
| 232 | 4 | sensor supply | voltage below normal or shorted low |
| 246 | 11 | brake pedal switch1 | switch not responding |
| 247 | 11 | brake pedal switch2 | switch not responding |
| 251 | 12 | injector power supply | low voltage for injector power supply |
| 251 | 2 | ECM failure | igniton power lost to ecm |
| 252 | 11 | ECU | incorrect engine software |
| 253 | 2 | ECU | customer or system parameters |
| 253 | 14 | ECU | OEM parameter not programmed |
| 311 | 14 | ATD | active regeneration inhibited due to low exhaust temperature |
| 314 | 3 | clean gas induction | CGI pressure sensor voltage above normal |
| 314 | 4 | clean gas induction | CGI pressure sensor voltage below normal |
| 315 | 2 | clean gas induction | CGI temp high |
| 315 | 3 | clean gas induction | CGI temp sensor voltage above normal |
| 315 | 4 | clean gas induction | CGI temp sensor voltage below normal |
| 316 | 0 | clean gas induction | CGI flow rate high |
| 316 | 3 | clean gas induction | CGI temp sensor voltage above normal |
| 316 | 4 | clean gas induction | CGI temp sensor voltage below normal |
| 316 | 11 | clean gas induction | CGI flow rate high |
| 316 | 14 | clean gas induction | CGI flow rate low |
| 317 | 5 | clean gas induction | CGI actuator shaft current below normal |
| 317 | 6 | clean gas induction | CGI actuator shaft current above normal |
| 324 | 0 | ATD | ATD differential pressure above limits |
| 320 | 0 | ATD | ATD filter temperature high |
| 320 | 1 | ATD | ATD filter temperature high |
| 320 | 11 | ATD | ATD filter temperature very high |
| 320 | 3 | ATD | ATD filter temperature sensor voltage above normal |
| 320 | 4 | ATD | ATD filter temperature sensor voltage below normal |
| 324 | 11 | ATD | ATD differntial pressure, high filter restriction |
| 324 | 3 | ATD | ATD differential pressure voltage above normal |
| 324 | 4 | ATD | ATD differential pressure voltage below normal |
| 324 | 2 | ATD | ATD differential pressure signal erratic |
| 324 | 1 | ATD | ATD differential pressure , filter restricted |
| 324 | 0 | ATD | ATD differential pressure above limits |
| 327 | 2 | ATD | ATD exhaust gas temperature 2 data drifted high |
| 327 | 3 | ATD | ATD exhaust gas temperature 2 voltage above normal |
| 327 | 4 | ATD | ATD exhaust gas temperature 2 voltage below normal |
| 332 | 3 | aftertreatment fuel pressure control | aftertreatment fuel pressure sensor voltage above normal |
| 332 | 4 | aftertreatment fuel pressure control | aftertreatment fuel pressure sensor voltage below normal |
| 332 | 11 | aftertreatment fuel pressure control | aftertreatment fuel presuure high |
| 333 | 5 | aftertreatment fuel pressure control | ARD solenoid current abovenormal |
| 333 | 6 | aftertreatment fuel pressure control | ARD solenoid current above normal |
| 334 | 5 | aftertreatment fuel actuator | ARD solenoid current below normal |
| 334 | 6 | aftertreatment fuel actuator | ARD solenoid current above normal |
| 335 | 5 | aftertreatment ignition | ARD ignition current below normal |
| 335 | 6 | aftertreatment ignition | ARD ignition current above normal |
| 336 | 3 | aftertreatment 2 fuel pressure | sensor voltage above normal |
| 336 | 4 | aftertreatment 2 fuel pressure | sensor voltage below normal |
| 336 | 11 | aftertreatment 2 fuel pressure | fuel pressure high |
| 341 | 5 | aftertreatment purge air actuator | ARD purge air current below normal |
| 341 | 6 | aftertreatment purge air actuator | ARD purge air current above normal |
| 349 | 1 | aftertreatment purge air actuator | ARD purge air pressure low |
| 349 | 7 | aftertreatment purge air actuator | ARD purge pressure not responding |
| 350 | 5 | aftertreatment air pressure control | ARD solenoid current below normal |
| 350 | 6 | aftertreatment air pressure control | ARD solenoid current above normal |
| 350 | 7 | aftertreatment air pressure control | ARD solenoid not responding |
| 356 | 11 | ATD | ARD failed to ignite |
| 357 | 11 | ATD | ARD loss of ignition |
| 360 | 11 | aftertreatment | parked regen manually disabled |
| 373 | 3 | ATD secondary differntial pressure | sensor voltage above normal |
| 373 | 4 | ATD secondary differntial pressure | sensor voltage below normal |