Honda Civic OBD 1 Codes Reading Tutorial

Honda Civic OBD 1 Codes Reading Tutorial

Accessing the trouble code:

• Ensure ignition switched OFF.
• Bridge 2-pin data link connector (DLC) terminals Fig. 1 .

NOTE: DO NOT bridge 3 or 5-pin data link connector (DLC) terminals.

• Switch ignition ON. 
• Count MIL flashes. Note trouble codes. Compare with trouble code table.

NOTE: No trouble codes stored if MIL illuminates continuously.

1. Trouble codes 1-9 are indicated as follows:
2. Individual short flashes display trouble code Fig. 2 [A]. 
3. A short pause separates each flash Fig. 2 [B].
4. A long pause separates each trouble code Fig. 2 [C]. 
5. For example: Trouble code 3 displayed Fig. 2 . 
6. Trouble codes greater than 9 are indicated as follows:
7. Long flashes indicate the 'tens' of the trouble code Fig. 3 [A]. 
8. Short flashes indicate the 'units' of the trouble code Fig. 3 [C]. 
9. A short pause separates each flash Fig. 3 [B].
10. A long pause separates each trouble code Fig. 3 [D]. 
11. For example: Trouble code 12 displayed Fig. 3 . 
12. Switch ignition OFF.
13. Rectify faults as necessary.

NOTE: If a trouble code is displayed but not listed in the trouble code table, suspect engine control module (ECM) fault.

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ERASING THE TROUBLE CODE INSTRUCTION

Switch ignition OFF. Remove bridge wire.

Remove BACK UP (RADIO) fuse (7,5A) from underbonnet fusebox for 10 seconds minimum:

D14A2, D14A5, D14A7, D14A8, D15B2, D15B7, D15Z1, D15Z3, D15Z8, B16A2 1995, D16B2, D16Y2, D16Y3, D16Y7, D16Y8, D16Z6, D16Z7, D16Z9, B18C4 - Fig. 4 .

D14A3, D14A4, D15Z6, B16A2 1995 , D16Y5 - Fig. 5 . Refit fuse.

Trouble codes may also be erased by disconnecting battery lead.

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LIST OF HONDA CIVIC OBD 1 CODES

Flash type	Fault location	Probable cause
1	Heated oxygen sensor (HO2S)/oxygen sensor (O2S)	Fuel pressure/pump, wiring short to earth/open circuit/short to positive, HO2S/O2S, ECM
3	Manifold absolute pressure (MAP) sensor - circuit	Wiring, supply voltage, MAP sensor, ECM
4	Engine speed (RPM) sensor	Wiring, RPM sensor, ECM
5	Manifold absolute pressure (MAP) sensor - signal	Intake leak, vacuum hose blocked, wiring, MAP sensor, ECM
6	Engine coolant temperature (ECT) sensor	Wiring short to earth/open circuit, ECT sensor, ECM
7	Throttle position (TP) sensor	Wiring short to earth/open circuit, TP sensor, ECM
8	Crankshaft position (CKP) sensor	CKP sensor, wiring short to earth/open circuit, ECM
9	Camshaft position (CMP) sensor	CMP sensor, wiring short to earth/open circuit, ECM
10	Intake air temperature (IAT) sensor	Wiring short to earth/open circuit, IAT sensor, ECM
12	Exhaust gas recirculation (EGR) system - control	Wiring, vacuum hose(s), EGR solenoid, EGR valve position sensor, EGR valve, ECM
14	Idle air control (IAC) valve - circuit	Wiring, supply voltage, IAC valve, ECM
15	Ignition amplifier - control circuit	Wiring, supply voltage, ignition amplifier, ECM
16	Injectors	Wiring, supply voltage, injector, ECM
17	Vehicle speed sensor (VSS)	Wiring, VSS, ECM
19	Transmission lock-up solenoid	Wiring, solenoid, ECM
20	Electrical load sensor	Wiring, electrical load sensor, ECM
21	Camshaft position (CMP) actuator	Wiring, CMP actuator, ECM
22	Camshaft position (CMP) actuator oil pressure switch	Wiring, CMP actuator oil pressure switch, ECM
23	Knock sensor (KS)	Wiring, KS, ECM
41	Oxygen sensor heater - circuit malfunction	Wiring short to earth/open circuit/short to positive, HO2S, ECM
43	Heated oxygen sensor (HO2S)/fuel supply system - circuit malfunction	Wiring, fuel pressure/pump/filter, injector, HO2S, ECM
48	Heated oxygen sensor (HO2S) - circuit malfunction	Wiring, HO2S, ECM
54	Engine speed fluctuation sensor	Wiring, engine speed fluctuation sensor, ECM

Thank You Very Much!