Buntinboy9

Hello all, hopefully someone can help me diagnose what is going on.

So my check engine light came on a while ago and I have been struggling to pull the code from it for some time now. It is NOT a blinking light and the car's driving characteristics and fuel consumption has NOT changed.

At first I stopped by auto zone and when I had them run the code, they stated that the OBD-2 port was not getting any power. I thought this was weird so I took it to O'Reilly's and they stated the same thing.

They mentioned that it might be the fuse for the accessory socket. I tried checking the socket and it appeared to not work. I checked ALL of the fuses on the entire car and none of them were bad. I even replaced the one fuse for the socket and still nothing. I pulled the socket (which had been loose for some time) and then plugged it back in and screwed it in tightly again.

From here I did some research and thought that it could be the accessory relay that had failed. I went and bought one from Auto zone and replaced it. After this was replaced, I drove the car back up there and when the scanner went to access it, it stated that it would not communicate (both at auto zone and O'Reilly's)! I am truly at a lost as to why the OBD-2 port will not communicate with a scanner. Does someone know why this isn't transferring the information?

I was able to short the OBD-2 port and get a blink code from it. This blink code registered at 9 - 0. I want to say that I read somewhere that this is common for an EVAP system CEL for Honda's. It makes me feel better that its just the EVAP system but I really want to get this figured out.

*** Modifications to the car currently ***

*K&N FIPK Intake
*Challenge 76ta-s catback exhaust
*Innovative Motor Mounts 75a? (Next stiffer setting from OEM)
*Espelir ASD Springs
*Wider rims and tires (949 6ULR 17x9 with 255's)
*Aftermarket radio that does cut out every once in a while. (I believe this to be a grounding fault and plan on pulling soon to check)
*LED Indicator lights (soon to be replaced back to OEM) and LED Dome lights that sometimes flicker.
*(Placeholder for any small mods that I may have forgot, feel free to suggest mods that could be causing issues)


So in summary here are my questions.
- Does anyone know why the OBD-2 Port would not have power, then have power after the accessory relay change and not be able to be read?
- Can anyone confirm the blink code for 9 - 0?
- Are there any common fixes in relation to the EVAP system that I could try at home to try and remedy this?
- If the problem is fixed blindly will the CEL remove itself or does that have to be reset every time?
- Should I take this to Honda to be read?
- Does Honda charge to have a car read?

Thank you for the time taking to read this post and even more thanks if you decide to respond. I am sure that some of these more general questions could be sourced in other posts but in the event that someone else is struggling with this now or in the future they can use this post as a resource.

In the mean time I will continue to actively search for the answer to this and update this thread in what I find.

Thank you,

Utah S2K

Many Scan Tools do not self adjust for Foreign or Domestic cars. Make sure they have have the scanner correctly set to Foreign. If it is set to Domestic you will have the no power Ito connector symptom.

Utah

Buntinboy9

Interesting. I will see if this makes a difference. Utah, I believe it was a post that you had commented on that discussed the accessory relay. Do you have any input with what else I am experiencing?

Thank you

Billman250

The OBDII port supplies power to the scan tool itself via power and ground. Did you test for both?

Does the CEL pass the KOEO test? (Key on engine off)

Should come on with initial key-on, then go out.

Buntinboy9

I'm new to the electrical side of things so bear with me (Civil Engineer here who never paid attention to that material because he "didn't need it", correcting my ways now).

I do not know if I tested the ground via the OBD-II port. I believe I did test the power though and that's how I confirmed that it was the accessory relay that was partially to blame. How would one test to see if the ground in the OBD-II port was not grounding?

I am not sure of what your asking when it comes to the KOEO test. I believe it comes on and stays on but I can't be for certain. What your saying is that if I turn the key to the starting position, the check engine light should come on for a certain time and then go off by itself? Are there any posts or articles I could read to learn more about this?

Signalflow

Had the same exact problem. Autozone, advanced, ect. Couldn't pull codes. Honda wanted 75 bucks. I just bought a Bluetooth adapter obd2 plug and used dash command app on my IPhone and I pulled codes no problems. Dash command does a ton more too. Check it out.

fernando_fdz

Like Billman250 said, the OBD-2 port is what powers the scan tool. To bypass this, you can find someone or someplace that has a scanner that is self powered and that should work for reading DTC's. Usually Autozone won't carry self-powered.

Another option is to find the power/ground issue.


Pin 4 is your ground and Pin 16 is your battery power.
Best way to check both of these of course is with a multimeter which you can buy at radioshack or wal-mart for about $20 (nothing fancy if you want to keep it simple).
I'd make sure you have power and ground directly at the OBD-2 port to make sure everything is okay. I wouldn't rely on the knowing the accessory socket is powered as the wiring or connection to the OBD-2 port could be to blame.

Another quick thing to check is the OBD-2 pins at the connector. Just make sure they're not splayed or anything. If there is poor tension on the pins then it may not make contact with the scan tool.