Diagnostic Trouble Code Definition

1994 Honda Civic DX, 4D Sedan, AutomaticSECTION Diagnostic Trouble Code Definition
DIAGNOSTIC TROUBLE CODE IDENTIFICATION

Code (1) System Affected Probable Cause
0 ECM No Signal To ECM
1  Oxygen Sensor (O2S) (D15B8 Federal Model) Problem In HO2S Circuit
1  Heated Oxygen Sensor (HO2S) (Except D15B8 Fed. Model) Problem In HO2S Circuit
3  MAP Sensor Electrical Problem In MAP Sensor
4  Crank Angle Sensor (CKP) Open Or Shorted Signal Circuit
5  MAP Sensor Electrical problem in MAP Sensor
6  Engine Coolant Temperature (ECT) Sensor Open Or Shorted Signal Circuit
7  Throttle Position (TP) Sensor Open Or Shorted Signal Circuit
8  Crank Angle Sensor (TDC) Open Or Shorted Signal Circuit
9  Crank Angle Sensor (CYP) Open Or Shorted Signal Circuit
10  Intake Air Temperature(IAT) Problem With Sensor
12  EGR System No EGR Action
13  Barometric Pressure (BARO) Sensor Problem With PA Circuit
14  Idle Air Control(IAC) Valve Open Or Shorted Signal Circuit
15  Ignition Output Signal Electrical Problem In Signal Circuit
16  Fuel Injector Problem In Fuel Injector Circuit
17  Vehicle Speed Sensor (VSS) Open Or Shorted Signal Circuit
19  A/T Lock-Up Control Solenoid Valve (Civic & Civic Del Sol) Problem In Lock-Up Solenoid Circuit
20 (2) Electrical Load Detector (ELD) Problem With ELD Circuit
21  Spool Solenoid Valve (Civic & Civic Del Sol) Problem With VTEC Spool Solenoid Circuit
22  VTEC Oil Pressure Switch Problem In VTEC Oil Pressure Switch Circuit
41  Heated Oxygen Sensor (HO2S) Heater (D15Z1 Federal Model) Problem With HO2S Circuit
41  Heated Oxygen Sensor (HO2S) Heater (Except D15Z1 Fed. Model) Problem With HO2S Circuit
43  Fuel Supply System (Except D15B8 Calif. Model) Problem With HO2S Circuit Or Fuel System
48  Heated Oxygen Sensor (HO2S) (D15Z1 Federal Model) HO2S Circuit Fault
(1)
If codes other than these are indicated, repeat self-diagnosis. If code(s) reappear, substitute a known good ECM, and recheck codes. If code(s) clear, replace ECM.
(2)
MIL does not come on when there is a malfunction in ELD circuit, but code is stored in ECM memory.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.