Just got my 2003 Accord Coupe automatic EX V6 + NAV 1 month ago. I love it.
The NAV system is very slick. It controls the radio, air conditioner and CD as well. The car is fast and handles great.
I drove the car for about a week and then parked the car in my garage and turned on the alarm system as I left for a 3-week vacation out of the country. When I returned I discovered I had a dead battery (1.7 volts). Nothing worked, everything was dead.
I jumped the car and it started right up. Only the alarm system started going and the NAV system wanted a code after it loaded software. You can see it loading sw on the touch screen.
I called the dealer and asked him how to stop the alarm system and the codes for the NAV and Radio. Stopping the alarm system was easy - put the key in the door, not the ignition dummy. Put the NAV codes in on the touch screen and use the radio tuning dial to enter the radio codes. Everything came up fine.
I asked the Honda Service rep if this should have happened during a 3-week vacation. I can leave my VW for a month and it will start. He said the battery would go dead within a week usually as the car has about 4 or 5 computer systems and the alarm system to keep going. I was surprised.
I called HondaUSA to find out if this is true. The lady on the phone checked with Honda Service and they said that is true. I asked how that could be. What could possibly be running to totally drain a battery within a week, much less 3 weeks? She could not give an answer. I asked her what is one suppose to do if you park the car at the airport and go on a 1 1/2-week business trip? Expect to come back to a dead car. I asked her to ask the service people as to how soon the battery will go dead if parked and left, but they would not give a specific time.
Has anyone ran into this problem or heard of a battery going dead with 3 weeks or within a week as the dealer said it will. I find it hard to believe there is this much running to drain the battery. I wanted to get some info from your guys before I go back to Honda and request more specific info in writing as to what is causing the battery to go dead so soon and why there is not a second battery to prevent this.

 

something is not going to sleep as it should...did you have any dealer installed accessories put in when you bought the car? also, any aftermarket accessories later?

you might have something like a defective glove box light switch, trunk switch, etc. something you wouldn't normally notice is staying on, since it's blocked from view.

 

Everything on the car is stock from the factory. Nothing else has been installed by anyone.

 

that's definitely not normal. i asked a couple techs here just now and they said you should have someone do a current draw test on the car. there is no way the normal draw on the battery would kill it in a week.

they suggested checking for lights on, glove box, trunk, etc as well, as i did in my previous post.

 

Well - I'm not saying ur experience is normal - but I do know thw factory batteries on the 2003 Acords are REALLY small, and not many amps at all. I put in an Optima Deep-Cycle in my coupe - and have never had problems letting my car sit for 2 weeks. BUt I expect that from that battery.

I'm not saying you need a new battery or an expensive Optima at that - but, surprisingly my car doesn't turn over as many times before stating when I put it in - but the ain reason I got it was becasue I put some more power drawing sound stuff in.

 

I heard that this is normal due to the security system and ongoing current to the computers. I know for a fact that this is also true with BMW's.