windshield wipers killing 2001 windstar battery??

[k1m0e]

i have a 2001 windstar for 4 trouble free years, only issue is that the battery has been replaced twice in 2 years and the starter.. it seems every year during winter the battery misteriously dies. i had the vehicle checked and the dealer is unable to solve the problem besides the usual your battery is dead speach and u need a new one routine.. just the other day i went out to start the vehicle and again no juice. i noticed that the windshield wipers were being blocked from going all the way down by ice and snow, i remember this from last year as well thinking it was odd.. after recharging the battery and clearing the snow from the wipers so that it could sit in the proper position i let the van sit for a couple of days. it started no problem.. then i tried a test, i put a block of wood preventing the wipers from going all the way down and then shut the van off.. next day the battery was dead again. coincidence, i dont know but i think the windshield motor is still trying to go down and thus drawing power from the battery even after the key is removed. another oddity is when the battery is almost dead, the floor interior lights are on, but not any other lights just the floor lights on the passenger and driver side... if i try to start the van with the battery in this state all the guages in the instrument panel and spedometer go right to the end, temp guage, fuel gauage all go to the end.. once the van has been boosted the final oddity shows up, the four way flashers then turn on. this problem only seems to happen once a year and i am convinced that the windshield wiper motor is the problem. if u have any comments please post.

[mark v]

My suggestion is to make sure you clean out the wiper area before shutting them off since you did a test and it failed it.

[Jelinski]

Sounds like you are on to something with the wiper motor block, although I am a bit surprised that the motor will take being stalled for so long without being 'toasted'. Sounds like someone at Ford did a pretty careful design on this.

For a quick check of the battery charge, grab a digital voltmeter and check the battery voltage with the engine off. When the battery is pretty well fully charged, you should see a voltage around 12.6 or so. When the battery voltage is down around 12.1 or 12.0, it's pretty well drained.
With the engine running, the charging system should keep the battery & system voltage around 14 to 14.5 volts.

As far as the crazy stuff (lights coming on randomly, etc) when the battery is very low, many of the things that used to be controlled by actual switches are now controlled by a 'body module', in other words, by a computer. When the voltage goes low, the computer gets erratic and does all kinds of unpredicable things.

I hope this helps!

Jim