I have an 05 TL AT with 90k miles. Near the end of a couple of long trips (over 200 mi) I was crusing at highway speed when all of the sudden the car jerked a bit and I lost throttle response. This happened about 5 times in 20 miles. Each time I moved the AT selector to see if that was the problem and it caught and I was able to continue driving. During these incidents the tack and speedo both went to 0. However the engine was still running as I never lost power steering or brakes. Also no lights came except for the check engine light on the dash.

I took it to the dealer and they told me I had a P0865, which is as ECM power circuit manfunction. The software had already been updated in the ECM, so they re-initialized it. This was a couple weeks ago and I haven't had a problem. Of course I haven't taken a long trip since it has been fixed.

I wanted to post this for others out there who have experienced the same symptoms.

 

Thanks for sharing!! That is what this site is all about.

 

My 2005 MDX check engine light came on the other day after I started the car just after refueling. I didn't have any symptoms before that point. Pulling the code (OBD port location was in front of my knee to the right of the steering column) showed P0685. After reading through this forum and several others, seems like the problem could be from:
1) bad battery
2) bad battery cables (corroded/loose)
3) bad ECM relays
4) bad ECM

I opened the hood and found that the positive (+) battery terminal was very corroded. Battery voltage showed about 12.4V. After cleaning the terminal (needed some fine sandpaper to get all of it off) and pulling both terminals out for about 15 minutes, I reconnected the terminals, started the car and put in my radio and nav codes. It's been 3 days and so far no more check engine light. Getting close to 170K miles, knock on wood.