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Dodge Neon 2000 es 4 cyl.

My Neon can be jumped to start but if it is left alone (not driven, just turning the engine doesn't keep it charged) for more than 12 hours the battery dies. Mechanic doesn't can't find a drain, the starter tests fine, the alternator tests fine, it's a new battery, but it still dies if the car is not driven in a day. The key off draw is only 0.002A and there is nothing after market on the car at all. I can jump the care and it turns over immediately. It doesn't die until it has been left alone for 12 hours or more.

If anyone has any ideas I'd be welcome to hear them. If you need more information let me know.  

please have your battery charged first..

lets start with the simple and cheep stuff...

do you have a digital volt meter... if you don't.. they can be had for 7 bucks to 25 bucks..

a lot of parts stores have these from innova for about 16 bucks..



harbor freight stores have these for about 20 bucks



either will last you for decades..


next.... i would take a digital volt meter...

set it to 20 volts DC scale...

start the engine and turn on the headlights..

1. test between the positive and the negative battery posts.  14.1 to 14.8 volts is expected.

2. test between the negative battery post and the engine block. 0.04 volts is expected..

3. test between the negative battery post and the body... 0.02 volts is expected..

4. test between the Engine block and the body..  0.02 volts is expected.

if you get 0.00 on the last 3 tests.. change the meter setting to 2 volts DC scale.. and retest.. the last 3...

this test takes about 2 minutes...

post your results by test number..

if you get more than the 0.04 or 0.02 volts on the display...

you have a bad ground between those parts..



why do this test....   bad grounds will stop any new car in its tracks...

why... electrons flow from Negative to positive...  if you loose a ground.. or it becomes intermittent..  you won't have any power for that circuit...  just like a table light when the plug falls part way out of the wall...  the light will go out..

also i have fixed a LOT of cars lately with that  2 minute test... some hot water and a stainless steel wire toothbrush ...

finding the ground connections.. removing them from where they are bolted down after counting how many wires are on each one..   wire brushing both sides of the ring terminals...   wire brushing the back side of the nut.. wire brushing the mounting pad...  washing with HOT water..  

putting them back on.. and counting to verify the number of wires is the same...

the verifying with the same test again...

do this test first.. then the following test..  

next... a parasitic draw test .. slightly different on OBD2 cars...

you will need some kind of battery disconnect switch..



you will need a digital volt meter like i posted above.. or your existing digital volt meter if it has a 10, 15 or 20 amp DC scale..

roll down the drivers window...

hook the disconnect switch on one side of your battery.. figure out how to attach one test lead to one side of the switch and the other lead to the other side..   plugged into the proper amps holes..

start the engine..  let it run a minute...   shut it off.. get out.. leave the window down.. lock the door as you normally wood..

look at your watch..   wait for 6 minutes..   after six minutes....  loosen the green knob so that ALL the current is flowing through your amp meter..    

this way it does not break the circuit to connect your meter in series..   there are things that take just over 5 minutes in many OBD2 cars to shut down..   this gives you a TRUE reading..   i would think that any residual current would be between 0.030 Amps DC and 0.020 amps DC...


the last few cars that i have worked on that had parasitic draw.. had car stereo problems.. where the aftermarket car stereo was pulling almost a quarter amp for some reason..

there was one 86 300ZX that drove another mechanic in the shop crazy.. it would come in on a tow truck several times a week with a totally dead battery..  turned out it was the drivers door alarm switch on the inside of the door lock..

it would ONLY cause a parasitic draw when you activated the factory alarm with the key in the door lock..