Hi, my daughter came home from college this weekend and while I was driving her car to the auto parts store to get oil and a filter, I noticed the check engine light was on. I had Autozone check it out for me and they gave me the following codes that showed up...p0740 & p0700
The car seems to be driving fine so is this something I need to be concerned about immediately or can I let it ride for a while? Thanks

 

I recommend viewing this thread to give you a few ideas. https://www.hondacivicforum.com/foru...ighlight=p0740

Post results here.

 

thanks for the link. I checked the lock-up control solonoid as in the link and that checked out ok. I then checked the 2p service connector for codes and the light blinked 7 times. I think it was the 1 second flashes which would mean "70" but there is no 70 on the code list. I don't really know what else to do at this time. I'm going to disconnect the negative battery terminal to make the light go out and ask my daughter to let me know if it comes back on.

 

Let her drive around for about 6-10 miles. That's about how long it should take for the codes to reappear. If they do reappear, try the jumper method again and check the codes again.

So there was no transmission code indicated by the D4 light? It's possible that it happened once and it was just an electrical hiccup. Codes remain stored until the computer is cleared.

 

Well, I just called her and she's about 20 miles into her drive back to school and the light hasn't come back on as yet. So far, so good. Maybe it's as simple as you said and it was just a blip. Wouldn't be the first time I've encountered that. Thanks again for your help.

 

Well, a year later, my daughter has graduated and since moved to Brooklyn. She wants me to sell her car since she doesn't need it anymore. I detailed it and was getting ready to post it for sale, but the engine light was back on. I checked the codes and they are the same as before. I checked the solenoid per the link you provided and the resistance is within specs and the solenoid clicks when jumped from the battery. I even removed the solenoid this time to check that the screens were clean. Everything checked out ok so I disconnected the battery to reset the codes. Is there anything else I could do to assure the "check engine" light won't come on again?