| CODE | VEHICLE | DEFINITION |
| 1 | 86-98 Civic 97-98 CRV 85-98 Prelude 94+ Integra | Oxygen Sensor "A" (Primary) defective circuit or unplugged / defective sensor |
| 2 | 86-87 Civic
| Oxygen Sensor "B" defective circuit or unplugged / defective sensor |
| 3 | 86-98 Civic 97-98 CRV 85-98 Prelude 94+ Integra | MAP Sensor (Manifold Absolute Pressure) defective circuit or unplugged / defective sensor |
| 4 | 88-98 Civic 97-98 CRV 85-98 Prelude 94+ Integra | CKP Sensor (Crankshaft Position Sensor) defective circuit or unplugged / defective sensor |
| 5 | 86-98 Civic* 97-98 CRV 85-98 Prelude 94+ Integra | MAP Sensor (Manifold Absolute Pressure) mechanical problem / disconnected piping * not 94-95 |
| 6 | 86-98 Civic 97-98 CRV 85-98 Prelude 94+ Integra | ECT Sensor (Engine Coolant Temperature) defective circuit or unplugged / defective sensor |
| 7 | 86-98 Civic 97-98 CRV 85-98 Prelude 94+ Integra | TP Sensor (Throttle Position) defective circuit or unplugged / defective sensor |
| 8 | 86-98 Civic 97-98 CRV 85-98 Prelude 94+ Integra | TDC Sensor (Top Dead Center) defective circuit or unplugged / defective sensor |
| 9 | 86-98 Civic 97-98 CRV 85-98 Prelude 94+ Integra | CYP Sensor (Cylinder) defective circuit or unplugged / defective sensor * invalid code for throttle body injection Hondas ** invalid code for V6 engines |
| 10 | 86-98 Civic 97-98 CRV 85-98 Prelude 94+ Integra | IAT Sensor (Intake Air Temperature) defective circuit or unplugged / defective sensor |
| 12 | 86-98 Civic 85-98 Prelude 94+ Integra | EGR Lift Sensor (Exhaust Gas Recirculation) defective circuit or unplugged / defective sensor * invalid code for non-equipped EGR valve vehicles |
| 13 | 86-98 Civic 97-98 CRV 85-98 Prelude 94+ Integra | BARO Sensor (Atmospheric Pressure) defective circuit or unplugged / defective sensor |
| 14 | 88-98 Civic 97-98 CRV 88-98 Prelude 94+ Integra | IAC Valve (Idle Air Control) defective circuit or unplugged / defective sensor |
| 15 | 88-95 Civic 88-95 Prelude 94+ Integra | Ignition Output Signal missing or defective ignition output signal |
| 16 | 88-95 Civic 88-85 Prelude 94+ Integra | Fuel Injector System defective circuit or unplugged / defective fuel injector |
| 17 | 88-98 Civic 97-98 CRV 88-98 Prelude 94+ Integra | VSS (Vehicle Speed Sensor) defective circuit or unplugged / defective sensor |
| 19 | 88-95 Civic 94+ Integra | Automatic Transmission Lock Up Control Solenoid Valve defective circuit or unplugged / defective solenoid valve |
| 20 | 88-98 Civic 97-98 CRV 92-98 Prelude 94+ Integra | Electrical Load Detector defective circuit or unplugged / defective sensor |
| 21 | 92-95 Civic 93-95 Prelude 94+ Integra | VTEC Solenoid Valve defective circuit or unplugged / defective solenoid valve * invalid code for non-VTEC engine ** invalid for V6 engine |
| 22 | 92-98 Civic 93-98 Prelude 94+ Integra | VTEC Oil Pressure Switch defective circuit or unplugged / defective oil pressure switch * invalid code for non-VTEC engine |
| 23 | 96-98 Civic 92-98 Prelude 94+ Integra | KS (Knock Sensor) defective circuit or unplugged / defective sensor * invalid code for V6 engine |
| 30 | 92-98 Prelude 94+ Integra | Automatic Transmission Signal: "A" / SEAF / SEFA / TMA or TMB defective circuit or unplugged / defective sensor * invalid code for 1996 |
| 31 | 92-95 Prelude | Automatic Transmission Signal "B" defective circuit or unplugged / defective sensor |
| 41 | 92-98 Civic 97-98 CRV 90-98 Prelude 94+ Integra | Primary Oxygen Sensor - Heater circuit malfunction |
| 43 | 92-95 Civic 90-95 Prelude 94+ Integra | Fuel Supply System defective or malfunctioning fuel supply system |
| 45 | 96-98 Civic 97-98 CRV 96-98 Prelude 94+ Integra | System Too Lean or Too Rich malfunction in the fuel monitoring systems |
| 48 | 92-98 Civic 94+ Integra | LAF Sensor (Lean Air Fuel) defective circuit or unplugged / defective sensor |
| 54 | 96-98 Civic 97-98 CRV 94+ Integra | CKF Sensor (Crankshaft Speed Fluctuation) defective circuit or unplugged / defective sensor |
| 61 | 96-98 Civic 97-98 CRV 96-98 Prelude 94+ Integra | Oxygen Sensor, Heated - Sensor 1 (Primary) high voltage, low voltage, or slow response |
| 63 | 96-98 Civic 97-98 CRV 96-98 Prelude 94+ Integra | Oxygen Sensor, Heated - Sensor 2 (Secondary) high voltage, low voltage, or slow response |
| 65 | 96-98 Civic 97-98 CRV96-98 Prelude 94+ Integra | Oxygen Sensor Heater (Secondary) malfunctioning or defective oxygen sensor heater |
| 67 | 96-98 Civic 97-98 CRV 96-98 Prelude 94+ Integra | Catalyst system Efficiency Below Threshold malfunctioning or defective catalyst system |
| 70 | 96-98 Civic 97-98 CRV 96-98 Prelude 94+ Integra | Automatic Transmission malfunction with the automatic transmission controls |
| 71 | 96-98 Civic 97-98 CRV 96-98 Prelude 94+ Integra | Cylinder 1 Misfire or a Random Misfire a condition is present that is creating a cylinder misfire |
| 72 | 96-98 Civic 97-98 CRV 96-98 Prelude 94+ Integra | Cylinder 2 Misfire or a Random Misfire a condition is present that is creating a cylinder misfire |
| 73 | 96-98 Civic 97-98 CRV 96-98 Prelude 94+ Integra | Cylinder 3 Misfire or a Random Misfire a condition is present that is creating a cylinder misfire |
| 74 | 96-98 Civic 97-98 CRV 96-98 Prelude 94+ Integra | Cylinder 4 Misfire or a Random Misfire a condition is present that is creating a cylinder misfire |
| 80 | 96-98 Civic 96-98 Prelude 94+ Integra | Exhaust Gas Recirculation insufficient flow detected |
| 86 | 96-98 Civic 97-98 CRV 96-98 Prelude 94+ Integra | ECT Sensor (Engine Coolant Temperature) circuit range / performance problem |
| 90 | 96-98 Civic 97-98 Prelude 94+ Integra | Evaporative Emission Control System leak detected in the fuel tank area |
| 91 | 96-98 Civic 97-98 Prelude 94+ Integra | Fuel Tank Pressure Sensor low input |
| 92 | 96-98 Civic 97-98 CRV 96-98 Prelude 94+ Integra | Evaporative Emission Control System insufficient purge flow |