Out of the blue, battery dead

[scottrappley]

Ok. Here is what I have found so far. First I have a 2003 explorer limited. I just drove it the day and everything was fine. 2 days later I got in it and tried to start it and the battery was dead. I checked the interior lights and doors and everything obvious. I could not find anything wrong. I took the hood plunger switch off to see if that was the problem. I thought maybe the light for underneath the hood was always staying on. The plunger switch opened and closed as it should with no power. I charged the battery up and then I took off the charger and put my meter on it. The battery is slowly draining. It is constantly coming down real slow. The battery is not old either, June of 2010. I am really baffled. I can only figure it is either a bad battery or it "appears" something is drawing it down. Any ideas??? Thanks.

 

[LMHmedchem]

Ok. Here is what I have found so far. First I have a 2003 explorer limited. I just drove it the day and everything was fine. 2 days later I got in it and tried to start it and the battery was dead. I checked the interior lights and doors and everything obvious. I could not find anything wrong. I took the hood plunger switch off to see if that was the problem. I thought maybe the light for underneath the hood was always staying on. The plunger switch opened and closed as it should with no power. I charged the battery up and then I took off the charger and put my meter on it. The battery is slowly draining. It is constantly coming down real slow. The battery is not old either, June of 2010. I am really baffled. I can only figure it is either a bad battery or it "appears" something is drawing it down. Any ideas??? Thanks.

If the bat isn't maintenance free, does it have enough water in it? There is a battery cover on mine, even though it isn't maintenance free. That is not a good idea since you have to disconnect the terminals to check the water levels and such. If there are ports for adding water, open them and check to make sure there is enough water. Add distilled if it's low, especially if the metal plates are exposed.

If it's losing power while connected to the system, you may also have a short somewhere.

LMHmedchem

 

[scottrappley]

Well here is what I have found so far. I disconnected the battery and the battery level stayed level so it is no problem with the battery. Something in the vehicle is drawing it down. I hooked the battery back up and went inside the vehicle and starting hitting the power windows and locks buttons on the doors. I went out and checked the battery and it "appears" that it is now not drawing down the battery. I wrote down the battery level and I will check it in another hour or so and see if it is maintaining. If it is ok then I am going to be really nervous about driving it in case of something shorting out again. I am now looking at one of the portable jump start stations. I think I really need to have one in the vehicle now in case this happens again and I am away from home. Boy what a problem to have. I will post more after I check the battery level out in awhile. Thanks for any help.

 

[scottrappley]

Update

Well the battery now is holding a charge. I have been checking it for hours and it has maintained. Must be some relay that was stuck I am guessing. I did go and turn the ignition on and then after a minute turned it off. I waited for the lights to go out and re-checked the battery. There was no drain. Guess I will just have to drive it and keep monitoring it. This is not a good problem to have. It could die at any time any place. I will have to get that portable power pack asap and keep it in the vehicle. I guess one of the downsides about having a vehicle with 134,x.. miles on it.

 

[NEWFS02X]

What i would do first is to fully charge the battery and then do a load test on it to confirm the state of the battery. I've seen fairly new batteries go kaput with a dead cell in it.

If the battery checks out ok and the terminals are corrosion free then maybe a drain test is in order.

This can be done with a test light connected to the battery neg and the negative lug (removed from the - post).

If the light comes on then there is a drain.

Now, there are certain circuits in the vehicle that require running on a very low amperage draw.

Start by pulling out the fuses one by one until the light goes out. That will tell you the circuit at least that is on that fuse. then you can check out each item on that circuit to eliminate.

A bright light shows a major draw , which of course it shouldn't be. A dim light...the opposite ..which could be one of the required 'live ' circuits such as the radio memory etc.

Just remember...if you are down there pulling out the fuses..make sure the door switch is pushed in so the interior lights don't come on. That would botch your amp draw test.

Also, wait a few minutes to make sure all items in the car have shut down first before pulling the fuses.

Hope this helps......John

 

[RickM]

This happened to me a few years ago. Turned out to be the Door Ajar switch. It would malfunction and turn the interior lights and/or alarm on randomly.

 

[scottrappley]

Well I am pretty sure it is not the door switch. The interior lights and the lights under the outside mirror do go off after a minute or so. I was thinking maybe a battery saver relay???? It bothers me that after I put the key in the ignition and played with some of the door lock/window switches that now the draw has gone away. I am not sure if the problem is related to the ignition or one of the window/lock switches. Even if it was related to the lock/wiindow swithces I thought the battery saver relay would cut power to those anyway???? Kind of confusing. Any more ideas?

 

[RickM]

Well I am pretty sure it is not the door switch. The interior lights and the lights under the outside mirror do go off after a minute or so.

So did mine...problem was intermittent and found by accident.

 

[scottrappley]

Hmmm. Interesting. Glad you said something about it being intermittent. It surely is possible that is the problem then. I went out and looked at the door looking for some sort of plunger but I did not see one. I saw a black plastic like arm located toward the bottom of the door. This arm actually goes inside the door panel. Is that where the actual door switch is located? How did you fix your problem, just replace that switch? Thanks again for the help.

 

[Rickademus]

My 2005 explorer has a 12 volt voltage drain with the neg terminal disconnected i disconnected every driver footwell fuse and under the bonnet fuse and relay and the light test light does not even go dim. Both front doors were open at the time of test maybe door light switch related.