1997 V6 Honda Accord Battery Problem

So…To start off this car has 300k miles on it and It is pretty incredible its still running to me, lol. But, last night when I went into work, I left the keys in the ignition in the “On” position, and locked my doors… The reason this happened is because I cannot open the car door from the inside so I have to roll the windows down to open the door on the outside. So when I pulled in I turned the engine off then switched it back ‘on’ to roll the windows down… then I had to lock the car door holding the outside handle and pressing the inside lock button… so apparently amongst all that i forgot the keys in the ignition and locked them inside…Fast forward 12 hours of work and the battery is DEAD… obviously so.

We try to jump it off a few times but I’m not getting ANY lights, none of the power stuff is working, save the horn. No dome lights, no power windows, no engine lights…NADDA… I take it to get it tested and they say the battery is bad and kept saying the polarity was reversed, which I’m no sure how that happened because I know I placed it on the correct terminals…

Fast-forward $100 and i hook up the new battery, and when I go to crank it …NOTHING…no LIGHTs, no locks… only the Horn works…

This couldn’t(shouldn’t) be the alternator right??

What could it be!?

Thanks in advance!

Check all fuses, both under the hood and under the dash (below and to the left of the steering wheel).

See if the 80 amp battery fuse is blown in the fuse box under the hood.

Tester

When a battery gets very low, it can reverse polarity. You need to check fuses.

Good ideas about the fuses above. Another idea to consider, sometimes “new” batteries have been sitting on the shelf long enough to become discharged. You may need to do an overnight charge of your new battery with a battery charger first. Try that, maybe it will start then. It’s a good time to use one of those battery post cleaning tools and thoroughly clean the posts and the connectors too.

Also, jumping a really dead battery, the process can sometimes damage an alternator diode. That wouldn’t typically cause the symptom you are experiencing, but if the alternator light stays on once you get the engine running, you’ll know why. Jump starting conked batteries is so grueling it can sometimes damage the ECM too, but in your case by your comments above I think you did it carefully so ECM damage is unlikely.

It seems there is a problem in the main power distribution area. Your vehicle is old enough that there may be some fusible links connecting power from the battery to areas of the car. These look like pieces of wire and are made to handle a certain amount of current. They are color coded in capacity and can burn out in the middle but it isn’t obvious it is bad just looking at it. Use a test light to check for power at each end of it. Other things to check are the fuses in the panel under the hood. Make sure they are all getting power on both sides of them using a test light probe. If that is okay you need to check the power input to the ignition switch and after it. It supplies power to the fuses in the dash fuse panel.

A few nitpicky details are absent but this era of Honda is under a Recall for ignition switch failure.
If this Recall has never been performed you can have it done free of charge at any Honda dealer.

Symptoms can vary but may involve a no-start condition, intermittent stalling, and so on along with lack of dashboard warning lights.