How To: Reading Check Engine Light (CEL) With Code List

lonewolf

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199?-2000 models
All models are equipped with an On-Board Diagnostic system (ODB). This facility is built into the PCM, and is designed to alert the driver to a system component fault which may result in a higher than normal emissions of harmful exhaust/fuel vapour gases and speed up the engine management troubleshooting procedure. Should an engine management component fail, the incorrect (or implausible) signal is recognised by the PCM, which stores a Diagnostic Trouble Code (DTC), and where appropriate, illuminates the Malfunction Indicator Light (MIL)/Check Engine Light (CEL) in the instrument cluster.
In order to retrieve any stored DTC's, either a fault code reader must be connected to the vehicles datalink connector (located above the Service Check Connector), or read from the MIL in the instrument cluster.



The service check connector (2-pin) is located under the dashboard, above the passenger side kick panel. By default it is inserted into a green rubber housing. for 92-95 models it is gray, 96-00 models its blue. The codes can be read by bridging the two pins in the service connector and reading the MIL on the instrument cluster (all models). Vehicles 2000 onwards are fitted with a 16-pin diagnostic behind the centre console on the passenger side. A fault code reader is required to retrieve or clear codes via this connector.
To view any DTC's stored in the PCM memory (without a code reader), fit a bridging wire into service check connector then turn the ignition switch to the ON position. If any codes are present, they will blink a sequence in the MIL to indicate a system or component failure.



The MIL will blink longer to represent the first digit and then will blink short for the second (for example 1 long and 6 short would be code 16). If the system has more than one problem, the codes will be displayed in sequence, there will be a pause, then the codes will repeat.

When the PCM sets DTC, the MIL will come on and trouble code will be stored in the memory. The trouble code will stay in the PCM until voltage to the PCM is interrupted. To clear the memory, remove the BACK-UP fuse from the fuse relay box located in the engine compartment for at least ten seconds. NOTE - This will also clear any radio presets/codes.

Common Diagnostic Trouble Codes
1 O2A - Oxygen sensor #1
2 O2B - Oxygen sensor #2
3 MAP - manifold absolute pressure sensor
4 CKP - crank position sensor
5 MAP - manifold absolute pressure sensor
6 ECT - water temperature sensor
7 TPS - throttle position sensor
8 TDC - top dead centre sensor
9 CYP - cylinder sensor
10 IAT - intake air temperature sensor
12 EGR - exhaust gas recirculation lift valve
13 BARO - atmospheric pressure sensor
14 IAC (EACV) - idle air control valve
15 Ignition output signal
16 Fuel injectors
17 VSS - speed sensor
19 Automatic transmission lockup control valve
20 Electrical load detector
21 VTEC spool solenoid valve
22 VTEC pressure valve
23 Knock sensor
30 Automatic transmission A signal
31 Automatic transmission B signal
36 traction control found on JDM ecu's
41 Primary oxygen sensor heater
43 Fuel supply system
45 Fuel system too rich or lean
48 LAF - lean air fuel sensor
54 CKF - crank fluctuation sensor
58 TDC sensor #2
61 Primary oxygen sensor
63 Secondary oxygen sensor circuit
65 Secondary oxygen sensor heater wire (black wires)
67 Cat Converter
71 random misfire cylinder 1
72 random misfire cylinder 2
73 random misfire cylinder 3
74 random misfire cylinder 4
80 EGR Valve/Line
86 ECT sensor - Cooling System
91 Fuel Tank pressure sensor
92 EVAP Solenoid/Valve/Vacuum Lines
 
Last edited:

NoWayBack91Si

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just curious...why is code 3 and 5 the same?
 


DaGFTDOne

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just curious...why is code 3 and 5 the same?
To answer for anyone else who might ask it probably is for a high or low voltage output. What that means I can't remember but it should make it more clear.
 

leachuan

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199?-2000 models
All models are equipped with an On-Board Diagnostic system (ODB). This facility is built into the PCM, and is designed to alert the driver to a system component fault which may result in a higher than normal emissions of harmful exhaust/fuel vapour gases and speed up the engine management troubleshooting procedure. Should an engine management component fail, the incorrect (or implausible) signal is recognised by the PCM, which stores a Diagnostic Trouble Code (DTC), and where appropriate, illuminates the Malfunction Indicator Light (MIL)/Check Engine Light (CEL) in the instrument cluster.
In order to retrieve any stored DTC's, either a fault code reader must be connected to the vehicles datalink connector (located above the Service Check Connector), or read from the MIL in the instrument cluster.



The service check connector (2-pin) is located under the dashboard, above the passenger side kick panel. By default it is inserted into a green rubber housing. for 92-95 models it is gray, 96-00 models its blue. The codes can be read by bridging the two pins in the service connector and reading the MIL on the instrument cluster (all models). Vehicles 2000 onwards are fitted with a 16-pin diagnostic behind the centre console on the passenger side. A fault code reader is required to retrieve or clear codes via this connector.
To view any DTC's stored in the PCM memory (without a code reader), fit a bridging wire into service check connector then turn the ignition switch to the ON position. If any codes are present, they will blink a sequence in the MIL to indicate a system or component failure.



The MIL will blink longer to represent the first digit and then will blink short for the second (for example 1 long and 6 short would be code 16). If the system has more than one problem, the codes will be displayed in sequence, there will be a pause, then the codes will repeat.

When the PCM sets DTC, the MIL will come on and trouble code will be stored in the memory. The trouble code will stay in the PCM until voltage to the PCM is interrupted. To clear the memory, remove the BACK-UP fuse from the fuse relay box located in the engine compartment for at least ten seconds. NOTE - This will also clear any radio presets/codes.

Common Diagnostic Trouble Codes
1 O2A - Oxygen sensor #1
2 O2B - Oxygen sensor #2
3 MAP - manifold absolute pressure sensor
4 CKP - crank position sensor
5 MAP - manifold absolute pressure sensor
6 ECT - water temperature sensor
7 TPS - throttle position sensor
8 TDC - top dead centre sensor
9 CYP - cylinder sensor
10 IAT - intake air temperature sensor
12 EGR - exhaust gas recirculation lift valve
13 BARO - atmospheric pressure sensor
14 IAC (EACV) - idle air control valve
15 Ignition output signal
16 Fuel injectors
17 VSS - speed sensor
19 Automatic transmission lockup control valve
20 Electrical load detector
21 VTEC spool solenoid valve
22 VTEC pressure valve
23 Knock sensor
30 Automatic transmission A signal
31 Automatic transmission B signal
36 traction control found on JDM ecu's
41 Primary oxygen sensor heater
43 Fuel supply system
45 Fuel system too rich or lean
48 LAF - lean air fuel sensor
54 CKF - crank fluctuation sensor
58 TDC sensor #2
61 Primary oxygen sensor
63 Secondary oxygen sensor circuit
65 Secondary oxygen sensor heater wire (black wires)
67 Cat Converter
71 random misfire cylinder 1
72 random misfire cylinder 2
73 random misfire cylinder 3
74 random misfire cylinder 4
80 EGR Valve/Line
86 ECT sensor - Cooling System
91 Fuel Tank pressure sensor
92 EVAP Solenoid/Valve/Vacuum Lines
it started with a short one, then 2 long and 2 short. Is this showing code 1 and code 22? Pls advise
 


DaGFTDOne

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it started with a short one, then 2 long and 2 short. Is this showing code 1 and code 22? Pls advise
Yes, not sure what to say for 1 but for 22 check your oil. Low oil pressure will trip it. I found that out cause mine was burning oil badly when I got rid of it. If I forgot to fill the oil it would trip that code.
 

highrollercivic

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how do you reset the ECU after fixing the problem, i have the service manual and followed how to do it on there but the code is still on
 

mu$h

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hi iv got a honda civic 1995 1.3 dx and am having problems fitting in a piperX air filter because i cant get a pipe that is big enough to sit on the carb can any1 help???!!!!!
 

EluSive2K

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okay... im confused. I got 1 blink, pause, 1 blink, pause, 7 blinks, pause, 16 blinks...... then it starts all over.. is that a code 1, 16 and 17? or am I all wrong? Please let me know.
 

EluSive2K

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is it the oxygen sensor, speed sensor, and injectors????
 

EluSive2K

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Dang... guess this is not the same clubcivic I used to be a part of...... Well.... Guess I will have to seek answers to questions elsewhere. See ya around guys. =)
 

Tom8

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okay... im confused. I got 1 blink, pause, 1 blink, pause, 7 blinks, pause, 16 blinks...... then it starts all over.. is that a code 1, 16 and 17? or am I all wrong? Please let me know.
i think you have a few different engine codes, i think the first one is 27. the 2nd one is 16? hopefully this helps but i dont know.:lol::lol::word:
 

Tom8

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stand corrected, there is no 27 error code so try to count the first set of flashes again.
 

maguiver77

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2000 civic code : 6 blinks Problem

Ok guys have a question for you. I was driving on the freeway and noticed my check engine came on. Then noticed that my water temp was pegged. I pulled over immediately and noticed steam. I popped the hood and noticed coolant all over the place. The radiator cap was not hot so I figured I blew a hose. I popped the cap and no coolant. So after letting it cool down for a bit a added some water and it started steaming. I put the radiator cap on and noticed steam coming from the engine ( it appeared to be from the engine) Couldn't really tell. After starting the car there was no smoke coming from the exhaust so I dont think i blew a head gasket. What do you think?
After getting towed home, I jumped the 2 pin connector and got flashes( 6 - ECT Sensor (Engine Coolant Temperature). Now could a faulty sensor cause the ecu to do something and make it over heat, or did the sensor go bad from the over heating?

Anyone ever have a problem like this? Could a thermostat be the problem? Thanks for any help.
 

95 EJ Coupe

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Ok guys have a question for you. I was driving on the freeway and noticed my check engine came on. Then noticed that my water temp was pegged. I pulled over immediately and noticed steam. I popped the hood and noticed coolant all over the place. The radiator cap was not hot so I figured I blew a hose. I popped the cap and no coolant. So after letting it cool down for a bit a added some water and it started steaming. I put the radiator cap on and noticed steam coming from the engine ( it appeared to be from the engine) Couldn't really tell. After starting the car there was no smoke coming from the exhaust so I dont think i blew a head gasket. What do you think?
After getting towed home, I jumped the 2 pin connector and got flashes( 6 - ECT Sensor (Engine Coolant Temperature). Now could a faulty sensor cause the ecu to do something and make it over heat, or did the sensor go bad from the over heating?

Anyone ever have a problem like this? Could a thermostat be the problem? Thanks for any help.
Your ECU can't/will never tell your engine to dump coolant. You have a serious problem though. Check your water pump.
 

JustJustin

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Hey guys my CEL light came on and showed this code:

41 Primary oxygen sensor heater

I replaced my oxygen sensor and the CEL came on again with that code. is the o2 sensor I bought faulty? it was a cheaper brand... or would it have something to do with the wiring to the sensor. I also noticed that there are these codes:

1 O2A - Oxygen sensor #1
61 Primary oxygen sensor

so does code 41 necessarily mean it's the o2 sensor that's faulty or is it something else? I imagine that if it was the o2 sensor that was messed up it would show either code 1 or 61. Any help on this would be greatly appreciated.
 


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