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Dead battery in new car

I have a 2008 Honda Fit. I recently went on a trip for two weeks and my car sat unused. When I returned, the battery was dead. The service man who came to jump start the car said that this was typical with new cars. The car’s computer continues to monitor all of the systems and draws down on the car battery. He said that this was the case with all new cars, although he sees a biased sample.

The Honda dealer said this was not unheard of althogh he hoped that my experience was a one time deal and that it would be ok on my next trip. This does not inspire confidence.

I have heard about two options – disconnec the battery or buy a battery starter. Which is the best or are there other options.

i doubt either reason was the truth.

in most cases like yours, a light was left on. like the visor “make up” light, the dome light, or the trunk light. in other words, a small wattage light, that you don’t normally see, and aren’t likely to remember to shut off.

You did not tell us how long the car sat unused. If more than two weeks it is possible for a battery to go dead, especially if you have the car outfitted with a collection of antitheft and GPS gadgets. If less than one week, something is amiss.

I think every car owner ought to own a battery charger or an emergency starter pack, even if he has never experienced any trouble. One never knows. For the car owner who allows his car to sit unused for weeks at a time, a solar trickle charger is a good bet.

I would get a dash solar panel that plugs into the cig lighter if you leave it for long periods. Battery loses about 1% of charge a day if not connected. Vehicles electronics should add another 1-2% to that. New cars may have a smaller battery to save weight.

The solar charger is a great idea IF the vehicle is parked outside, rather than garaged, and IF the cigarette lighter socket is “hot” when the ignition is turned off.

On both counts, I would not be able to benefit from a solar battery charger, and I would urge potential buyers to find out if their cigarette lighter socket is “hot” when the ignition is off before investing in one of these devices.

I have heard this before. In fact, my 1995 Caravan had a master breaker you could pull for just this purpose. There are some electronics that are constantly in the on state (for example the radio receiver for the remote door locks). Ask the service person to show you where the breaker is that you can pull if you are going to park the vehicle for a long time.

I would get a solar charger and make sure all the lights like the glove box or trunk light are off.

Modern cars don’t all do that, but they are more likely to have the problems than say a 1970 car.

Disconnecting the batter can create its own problems.

Both were right. Yes there are things running with the ignition off, but two weeks should be cause a problem. Yes he does hope it will be OK on your next trip.

That said I would suggest having a auto parts store give your battery and charging system a free test. Keep in mind that running a battery down, even once can cause some damage to an otherwise good battery.

Good Luck

First of all, did they give you a new battery? The old one was probably damaged.

I had this problem in a new Jetta. First battery died in a week. After that I lost a battery every year or so until I figured out the dome light was not going out occasionally. If this happened and I didn’t use the car for a few days, dead battery. Finally fixed by leaving the dome light off. By this time the car was out of warranty.

All of the electronics on a modern car go into a sleep mode after the key has been off for a while (minutes to an hour). In the sleep mode they draw very little current. So if everything is operating as designed, your car should be fine for 2 wks or more. How much more depends on the design. Your dealer might know.

Have the dealer do a key-off current test. This involves connecting an ammeter in the battery circuit, turning the key off, and waiting an hour before making a measurement. have him check that number (and let us know) against the spec, probably around 50mA. Note that opening a door or whatever starts the 1 hour time over again.

If it is out of spec, it’s an easy matter for him to track down the problem.

Disconnecting the battery resets the computer, the radio codes, and god knows what else.

This car is under warranty. If your dealer won’t perform these steps, go to a different dealer. Or talk to the zone manager.

Things like battery switches and chargers are all well and good, but this is a new car and it should work correctly.

Another possible issue with disconnecting the battery: I think some models’ door locks are entirely electrically operated. Turning the key in the lock does not open the lock mechanically. Rather, it signals the computer to activate the electric lock-opening solenoids. So, if no battery, doors will not unlock.

I base this on the experience a friend had with a circa 2000 Camry whose battery went dead. The locks would not open. Somebody had to undo some body work under the grill to get to where they could open the hood to hook up jumper cables.

I’d love to learn that I am completely wrong.

The ones I’ve seen also have alligator clips so you can clip them directly onto the battery.

I would suggest maybe getting the battery tested. If your car sat on the lot for a long time before you bought it, the battery may have died then and if it stayed discharged for a long time it may have been damaged and may be weak today.

I doubt that something being left on was the cause since most cars today ( maybe not this car) come equipped with a electrical shutoff after so many minutes of idleness when something is left on. I have seen this before. It would help if you/we knew when you got the car from the dealer and it being left for 2 weeks unused. It would make a difference.

They don’t totally shutoff. See my note above re key-off current.

When the car talk guys reviewed the VW Touareg and has a dead battery they had to have it towed. The security system locked the key in the ignition, and they couldn’t open the rear compartment (or any of the doors) where the battery was located.

That shouldn’t happen that soon with a new car. You should get a new battery and it should be checked for a draw. On the Acura’s there have been reports of dead batteries. Some thought it was defective Honda batteries, a seat warmer switch malfuntioning, but most seemed to trace it back to a glitch in the outside temperature sensor. Seems like when it flat lines and doesn’t read, the computer goes into an endless loop and drains the battery. It should go for a month or more with no problems.

The car sat for two weeks exactly. While the car does have an added alarm, I turned it off when travelling since I would not be there to hear it. But as the dealer explained, the computer does continue to monitor tire pressure, gas, etc, even if I am not driving it. thanks for the advice about the charger.

I bought the car at the end of December. The dealer did not have the color I wanted so they got a car from another dealer about 100 miles away. I had, as I recall, about 1000 miles on it before I went on the trip, February 1. thanks

I will call the dealer and see if this can be done. thank you

Maybe I was lucky. I had disabled the security lock system during my trip. I have keyless access and it worked even though the battery was dead.