Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicator Light (MIL) and
#26
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Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
I have a 1992 Honda Accord Ex where the CEL only comes on when driving. Takes about 1-2 mins before it comes on. What's strange is when I start the car and let it idle (sometimes up to 20 mins or more) the light doesn't come on. Any ideas on why this happens? Also, the cars needs to be inspected and I was wondering do they let the car idle during the inspection or accelerate the engine? I will try to find the code using the method in the previous thread.
#28
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Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
I have a 1998 Honda Accord LX 4 cyl with about 130000 miles. The light to the AC control unit would go off and on while driving. When the lights go off, the AC nor the heater would work. However, when the lights to the AC control unit would come on, everything would work fine. I read on another thread that you can run a self diagnostics by holding the recirculation button and the recirculation light would start blinking out codes. I was wondering if you would use the same method to read OBD-II for those blinking light and determine the error code. Thanks
#29
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
Okay, I'm still lost and hope someone can point me in the right direction before I waste any more money. On my 1996 Honda Accord EX, my CEL is on for multiple cylinder misfire, OBD-II codes 1300, 301,302,303,304. checked CEL codes and got the same. Problem is, what is causing it?? Any ideas?? Put in new plugs, Cap and rotor and even changed the distributor with one from a salvage yard because someone (a mechanic) told me that the coil was probably bad? This is the only thing holding me back from getting a sticker.
#30
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
Okay, I'm still lost and hope someone can point me in the right direction before I waste any more money. On my 1996 Honda Accord EX, my CEL is on for multiple cylinder misfire, OBD-II codes 1300, 301,302,303,304. checked CEL codes and got the same. Problem is, what is causing it?? Any ideas?? Put in new plugs, Cap and rotor and even changed the distributor with one from a salvage yard because someone (a mechanic) told me that the coil was probably bad? This is the only thing holding me back from getting a sticker.
#31
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
Can I add to the pile?
I have a 93' accord with CEL coming on after engine is warm. giving me codes
12 and 43. I'm getting poor gas mileage 22-25mpg. 130,000 miles. No other tell tale signs other than MPG and CEL. You all think EGR valve replacement as first step or O2 sensor or something I'm missing? Please help!
Thanks for this thread by the way.
I have a 93' accord with CEL coming on after engine is warm. giving me codes
12 and 43. I'm getting poor gas mileage 22-25mpg. 130,000 miles. No other tell tale signs other than MPG and CEL. You all think EGR valve replacement as first step or O2 sensor or something I'm missing? Please help!
Thanks for this thread by the way.
#32
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
ok, i am at my wits end with my car. i am not able to post a new thread up til i am a member for 15 days with 5 posts or some crap like that and i don't have that kind of time, so what better than to ask on a relevant thread... i have a 1993 honda accord with the MIL on. i performed the check engine light diagnostic procedure of first pulling the code (code 6, ECT circuit malfunction). checked the resistance of the ect itself at normal operating temp (ranges from 400-500 ohms depending on if the thermostat is open or not) which is normal resistance at normal operating temp. that is to say after replacing the sensor (old sensor had 0 ohms which is either open or shorted, it being a thermistor). i have 11.46 reference volts (supposed to be at approx. 5 volts). so pretty much i have battery voltage (battery is slightly weak) as my reference volts at the sensor. to find out where there might be a direct short i isolated sensor side of the circuit from the ecm side by snipping the reference wire, stripping a small section of the insulation of the wire back about a 1/4" on the sensor side and the ecm side. i had 0 volts on the sensor side and 11.46 volts on ecm side. replace the ecm right? apparently not. i ordered an ecm the other day and it was shipped priority mail and came in today. i installed the new ecm, started it up, the check engine light stayed off for all of 5 seconds then BAM!!!! there it was again. i don't know where else to turn. it is a manual transmission so code 6 does not apply for the tcm as i do not have a tcm on my car (tcm is for A/T only). there is no more diagnostic procedures going down the diagnostic tree beyond what i have already done other than referring to code 6 for the tcm which, once again, does not apply. any ideas? your help would be greatly appreciated. oh and not to mention my idle is acting as if my IAC (idle air control valve) is acting up. i have cleaned it out several times and it doesn't help at all. (i am a tech by the way, just a very frustrated tech at this point with this car)
Last edited by @%#$er; 04-28-2011 at 08:24 PM. Reason: adding on forgotten content
#33
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
The resistance spec for operating temperature for the ECT is between 200 and 400 ohms. As you said, you shoult have a 5 volt reference voltage at the ECT. If you seperated the wire at the ECM and still have battery voltage this indicates a problem with the ECM.
Find a KNOWN GOOD ECM somewhere and recheck. My next idea would be a gremlin is living inside the ECM screwing with you.
Find a KNOWN GOOD ECM somewhere and recheck. My next idea would be a gremlin is living inside the ECM screwing with you.
#34
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
my civic is a b-18c jdm gsr that has been pretty built for performance but my check engine light is on due to a trouble code p0135. ive replaced both o2 sensors just to be safe, but the thing is my scanner reads no codes when the key is turned forward to acc, however when the car is running thats is when the trouble code p0135 kicks on. ive come to the conclusion that my car is running too rich and thats why the code only reads when the car is running? however im not too sure on how to fix it? could someone maybe point me in the right direction?
#35
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
P0135 points to the heater circuit in the o2 sensor, not the sensor detecting rich or lean conditions. The heater circuit heats up the sensor so it can start detecting lean/rich conditions sooner than if it just relied on the exhaust heat. Since you already replaced them, I would check the wiring harness next. I believe you will have 4 wires, 2 are the sensor output, 2 are power for the heating element. Find out which 2 are for the heater (wiring diagram), check them for 12V (I believe the ignition can just be 'on', but you don't have to have the car running). My bet is it's not there. Did you check fuses?
#36
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
I'm assuming you replaced the sensor with a factory component. The two black wires are the heater circuit. The white and green wires are the sensor signal. Factory wire colors, of course. The sensor should ohm around 4 ohms, I think.
Most heaters fail in a open-circuit fashion. But, some heaters will fail by going short circuit before they go open. When this happens the fuse can fail. Obviously, you should ohm the heater in the sensor before replacing the part as they are very expensive. If you determine the sensor is faulty and P0135 comes back after replacement there is a pretty good chance the sensor caused the fuse to fail.
Check the fuse.
Most heaters fail in a open-circuit fashion. But, some heaters will fail by going short circuit before they go open. When this happens the fuse can fail. Obviously, you should ohm the heater in the sensor before replacing the part as they are very expensive. If you determine the sensor is faulty and P0135 comes back after replacement there is a pretty good chance the sensor caused the fuse to fail.
Check the fuse.
#38
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
I'll assume you have a 90-95 (ish as the 96-97 have both ways ODB-I and OBD-II).
Once you have the two pin connector - insert the clip/jump to the female pins of the two wire connector. Turn the key to "On/Pos II" (don't start the engine).......start counting flashes from any of the "lights" - ABS, SRS, D4 is an auto trans or CEL.
Once you have the two pin connector - insert the clip/jump to the female pins of the two wire connector. Turn the key to "On/Pos II" (don't start the engine).......start counting flashes from any of the "lights" - ABS, SRS, D4 is an auto trans or CEL.
#40
MM Gruppe B
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
Adding some TCU codes for clarification.
'90-'97 model OBD I TCU codes(Using two wire blue connector.)
'H4A' transmission. (known as AOYA, BOYA, MPJA, MP1A, etc etc.)
1. Solenoid Valve A Lockup Control
2. Solenoid Valve B Lockup Control
3. TPS*D4 may or may not light*
4. VSS
5. Console Switch
6. Console Switch *D4 does not light*
7. Solenoid Valve A Shift Control
8. Solenoid Valve B Shift Control
9. NC sensor
10. Thermo sensor
11. Ignition Coil *D4 does not light*
12. Not Used
13. Non Specific, Possibly BARO sensor.
14. FAS-wire *D4 does not light*
15. NM sensor *D4 does not light*
***TECHAUTO Has the following three codes listed as potential alternatives for later model transmissions. These may be non-Accord codes.***
13. Main shaft speed pulse generator open or shorted.
14. Linear (line pressure control) solenoid open or shorted.
15. Kickdown switch circuit shorted.
'98-'02 OBD I(format) TCU Codes. (Using two wire blue connector.)
B7XA(2.3) & M6HA(3.0)
*These are the added codes with the later models/OBDII cars, use in conjunction with the above 15 TCU codes*
16. A/T Clutch Pressure Control Solenoid Valve A
22. Shift Solenoid Valve C
23. A/T Clutch Pressure Control Solenoid Valve B
25. 2nd Clutch Pressure Switch **D4/CEL do not light!**
26. 3rd Clutch Pressure Switch **D4/CEL do not light!**
40. Lock-up Control System *D4 does not light*
41. Shift Control System *D4 does not light*
45. Mechanical Problem in Hydraulic System
46. Mechanical Problem in Hydraulic System
47. Mechanical Problem in Hydraulic System
'98-'02 OBD II TCU Codes.
B7XA(2.3) & M6HA(3.0)
P0700. If there is a AT issue this code will be present, it is non specific.
P0715. NM sensor, Mainshaft Speed sensor.
P0720. NC sensor, Countershaft Speed sensor.
P0730. Shift Control system *D4 does not light*
P0740. Lock-up Control System *D4 does not light*
P0753. Shift solenoid Valve A
P0758. Shift solenoid Valve B
P0763. Shift solenoid Valve C
P0780. Mechanical Problem in Hydraulic System
P1705. Transmission Range Switch short to ground.
P1706. Transmission Range Switch open. *D4 does not light*
P1738. 2nd Clutch Pressure Switch.**D4/CEL do not light!**
P1739. 3rd Clutch Pressure Switch.**D4/CEL do not light!**
P1750. Mechanical Problem in Hydraulic System
P1751. Mechanical Problem in Hydraulic System
P1753. Torque Converter clutch solenoid valve
P1768. A/T Clutch Pressure Control Solenoid Valve A (known as the CPC or LINEAR valve)
P1773. A/T Clutch Pressure Control Solenoid Valve B (known as the CPC or LINEAR valve)
As noted not all faults will illuminate the D4 to indicate a trouble. And some don't indicate the CEL either. Thus if your car is running off or shifts funny, but you do not have a flashing D4/CEL you should always check for stored codes regardless.
*** Possibly codes are shared with 92-01 Prelude, 95-01 Odyssey, and 93-99 Rover 600
****Need to verify if '95-97 C27 cars share the above codes.
'90-'97 model OBD I TCU codes(Using two wire blue connector.)
'H4A' transmission. (known as AOYA, BOYA, MPJA, MP1A, etc etc.)
1. Solenoid Valve A Lockup Control
2. Solenoid Valve B Lockup Control
3. TPS*D4 may or may not light*
4. VSS
5. Console Switch
6. Console Switch *D4 does not light*
7. Solenoid Valve A Shift Control
8. Solenoid Valve B Shift Control
9. NC sensor
10. Thermo sensor
11. Ignition Coil *D4 does not light*
12. Not Used
13. Non Specific, Possibly BARO sensor.
14. FAS-wire *D4 does not light*
15. NM sensor *D4 does not light*
***TECHAUTO Has the following three codes listed as potential alternatives for later model transmissions. These may be non-Accord codes.***
13. Main shaft speed pulse generator open or shorted.
14. Linear (line pressure control) solenoid open or shorted.
15. Kickdown switch circuit shorted.
'98-'02 OBD I(format) TCU Codes. (Using two wire blue connector.)
B7XA(2.3) & M6HA(3.0)
*These are the added codes with the later models/OBDII cars, use in conjunction with the above 15 TCU codes*
16. A/T Clutch Pressure Control Solenoid Valve A
22. Shift Solenoid Valve C
23. A/T Clutch Pressure Control Solenoid Valve B
25. 2nd Clutch Pressure Switch **D4/CEL do not light!**
26. 3rd Clutch Pressure Switch **D4/CEL do not light!**
40. Lock-up Control System *D4 does not light*
41. Shift Control System *D4 does not light*
45. Mechanical Problem in Hydraulic System
46. Mechanical Problem in Hydraulic System
47. Mechanical Problem in Hydraulic System
'98-'02 OBD II TCU Codes.
B7XA(2.3) & M6HA(3.0)
P0700. If there is a AT issue this code will be present, it is non specific.
P0715. NM sensor, Mainshaft Speed sensor.
P0720. NC sensor, Countershaft Speed sensor.
P0730. Shift Control system *D4 does not light*
P0740. Lock-up Control System *D4 does not light*
P0753. Shift solenoid Valve A
P0758. Shift solenoid Valve B
P0763. Shift solenoid Valve C
P0780. Mechanical Problem in Hydraulic System
P1705. Transmission Range Switch short to ground.
P1706. Transmission Range Switch open. *D4 does not light*
P1738. 2nd Clutch Pressure Switch.**D4/CEL do not light!**
P1739. 3rd Clutch Pressure Switch.**D4/CEL do not light!**
P1750. Mechanical Problem in Hydraulic System
P1751. Mechanical Problem in Hydraulic System
P1753. Torque Converter clutch solenoid valve
P1768. A/T Clutch Pressure Control Solenoid Valve A (known as the CPC or LINEAR valve)
P1773. A/T Clutch Pressure Control Solenoid Valve B (known as the CPC or LINEAR valve)
As noted not all faults will illuminate the D4 to indicate a trouble. And some don't indicate the CEL either. Thus if your car is running off or shifts funny, but you do not have a flashing D4/CEL you should always check for stored codes regardless.
*** Possibly codes are shared with 92-01 Prelude, 95-01 Odyssey, and 93-99 Rover 600
****Need to verify if '95-97 C27 cars share the above codes.
Last edited by MAD_MIKE; 07-13-2014 at 02:46 AM.
#41
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
I don't know if this is still open, but I used a pocket scanner and came up with 3 codes, which your post was more than helpful in assisting me with. I am not aware of what these mean, and if since I have cleared them, I will be able to Pass inspection. P1456- Evap emission control system leak detected, in the fuel tank area. P171-System too lean? malfunction in the fuel monitoring system; and P420- Catalyst System malfunction or defective.efficiency below threshold. I know this car has some issues- I need an ignition switch, and a heater core, currently it is pinched off to prevent leaking. Can anyone explain to me what to do to fix these codes? p.s I just filled my tank, and was seriously hoping that some of this could be a gas cap problem! any help is appreciated
#42
MM Gruppe B
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
This thread is just for listing codes, their description and what may be the most common issue related to a given code.
P1456 can simply be caused by a loose gas cap, defective cap, or leaking seal or EVAP lines to the tank.
P0171 is for a running lean condition. Check fuel pressure, if it is low check if it is because of a faulty fuel pressure regulator, clogged fuel filter, or failing fuel pump.
P0420 is for catalyst inefficiency. Does not mean the cat is dead. Fix all other codes before looking at this. P0171 issue will cause the catalyst too not work properly as the catalyst can only function properly if the engine is close to stoich.
P0171 is for a running lean condition. Check fuel pressure, if it is low check if it is because of a faulty fuel pressure regulator, clogged fuel filter, or failing fuel pump.
P0420 is for catalyst inefficiency. Does not mean the cat is dead. Fix all other codes before looking at this. P0171 issue will cause the catalyst too not work properly as the catalyst can only function properly if the engine is close to stoich.
#43
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
Hello everyone. This is my first message.
I'm in trouble with my Accord Tourer 2.4 With GPL. Have 80.000Km and the last week every 5 minutes i receive a message like this:
DTC Service
DCT B2375
PA74
I didn't find anything about this (only a webpage dedicated to Honda civic and someone talk about the seat but i don't think is related).
Can you try to tell me what append? thanks
I'm in trouble with my Accord Tourer 2.4 With GPL. Have 80.000Km and the last week every 5 minutes i receive a message like this:
DTC Service
DCT B2375
PA74
I didn't find anything about this (only a webpage dedicated to Honda civic and someone talk about the seat but i don't think is related).
Can you try to tell me what append? thanks
#44
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
1998 Accord EX Sedan: I have what I believe is a CEL code 57 or 67. Lists that I've seen show only a 67 code. When I jump the OBD-II connector, it gives me an initial blink, then 5 long and 7 short blinks. The first blink of the 5 long blinks comes immediately after the initial blink when I first turn it on, so I'm a bit confused if it's 57 or 67. Since there's no code 57, it has to be 67.
#45
Honda-Tech Member
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
Short blinks are counted first when you look at reading the DTcodes through the CEL flashes.
So if it is one quick flash immediately followed by 5 long that would be a code 15 and then 7 quick would be a code 7.
7 = TPS
15 = Ignition input (even though I can't seem to find it cross referenced in the OBDII codes)
So if it is one quick flash immediately followed by 5 long that would be a code 15 and then 7 quick would be a code 7.
7 = TPS
15 = Ignition input (even though I can't seem to find it cross referenced in the OBDII codes)
#46
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
I gotta say, the buzz around trouble codes and reading them reminds me of a very important balance between cars and their problems. It's like this sort of "thats that' and its like..."yeah"
#47
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
Short blinks are counted first when you look at reading the DTcodes through the CEL flashes.
So if it is one quick flash immediately followed by 5 long that would be a code 15 and then 7 quick would be a code 7.
7 = TPS
15 = Ignition input (even though I can't seem to find it cross referenced in the OBDII codes)
So if it is one quick flash immediately followed by 5 long that would be a code 15 and then 7 quick would be a code 7.
7 = TPS
15 = Ignition input (even though I can't seem to find it cross referenced in the OBDII codes)
#48
Honda-Tech Member
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat
So after reading that and going by your description you have a code 1 and 57 or 1, 50 & 7......
You might want to verify the number of flashes or just hook up a scan tool and get the more accurate OBDII P Codes. Could it be a 5 - 7 abs or a tcu code??? Is the CEL the only light that is flashing?
#50
Re: Check Engine Light codes (CEL) Diagnostic Trouble Codes (DTC) Malfunction Indicat