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Something is draining the battery when the ignition is turned off.
An interior light left on is enough to drain the battery overnight enough so that the engine would not start. You would have some power left, but not enough to run the starter.
It could be a trunk light too. It could be brake lights staying on (I guess you would have noticed that).
BotXXXXX XXXXXne is, you need to charge the battery and run some tests to determine what is still using power when everything is off.
it may be a bad ignition switch too. If the electrical part of ite ignition switch is bad, it may not make proper conttact to run the starter, and when you take teh key out, some power may still stay on where it is normally off.
When the starter is not working from the key, you can bypass the key by connecting the starter little connector to the battery positive terminal, or to the big terminal on the back of the starter right next to the little one. Make sure the car is in park or neutral and something blocking the wheels, so there is no chance of the car starting to move when you run the starter. Use heavy gauge jumper wire or something to make the jump connection, there is a lot of power going through the wire. Sparks WILL fly on contact, it's normal. If the starter works like this but not from the key, then there is power loss or a break in the wiring from the ignition switch to the starter little terminal. Or like I said, the ignition switch has gone bad.
i'm sorry the ign switch didn't solve your problem. It certainly was a plausible cause.
I thinkt the radiator fan normally runs even after the engine has been shut off, until the coolant temperature sensor says the coolant has cooled down enough. The power gets fed directly from the battery via a relay. If the temperature switch goes bad and "hangs", it will cause the fan to turn at all times, even with the key removed from the ignition. You should hear it run though?
The fan could be seized or otherwise inoperational, yet still drawing power when the motor is trying to turn. You would have heard the fan run if it was running and the engine was not.
You should charge the battery with a wall charger before jump starting the car. Modern alternators aren't designed to charge a near empty battery repeatedly, it's too much to ask. They may overload. They're good for maintaining a charge, which is what their main job is anyway. You can also charge the battery with the jumper cables, allow it to charge for 20 minutes at least before trying to jump start. There needs to be some life left in the battery. Jumper cables are often not thick enough to carry full current to the battery to run the starter and everything else in full power.
Try again with a fully charged battery, see if it starts and runs. I know you tried to charge the battery at least a little bitr before with no luck. Then you can continue tracking down the root cause of the drain. Inspect the radiator fan, see how it works. If you let the car sit at idla after a longer drive, the fan would probably come on after a while, and then it should turn off again. If this cycle works as described, then I don't know how there could be a draw on that fuse. Stuck radiator fan relay maybe?
What exactly happens when the battery HAS power, and the engine still won't start?
Does the starter turn the motor over at all? Does it just click, or does it seem that no power at all is going to the starter? (no clicking)
I'll Opt Out to allow other experts to offer their assistance, in case someone knows more things to check.
Hi there I'm Scott,
I'm so sorry to hear about your vehicle problems, this is a bad time of the year to have this happening. I think there might be a few things we can look at. First let me understand this just a little more. When you pull the fan fuse your battery draw goes completely away? Second, when exactly did you replace the battery? Third, have you taken a piece of sandpaper or a terminal cleaner to battery connections and cleaned them thoroughly before hooking the battery up? Forth, have you went back over the component wiring and connections on the component's you replaced? Fifth, with the vehicle cold and the battery unhooked due to safety reasons have you spun the fans to make absolutely sure you have no obstructions stopping them and that the motors spin freely? Sixth, have you fully charged your battery(like charging it on a good charger for several hours before trying it?) I really hope we can figure this out without you having to spend anymore money. If you can get back with me soon that would be good, I'm heading out of town this afternoon and returning tomorrow afternoon. Hopefully we can get this done before I leave.
Well I totally understand your dilema. First off I would take a clean the battery connections, because sometimes even though they look quite clean they aren't. And then just a 30-40 minute charge on your battery is not getting it done, it usually takes several hours for a battery to charge up right and depending on the amperage of your charger possibly even more time. And then there is something that comes to mind that I've been running into quite a bit lately. If after you let it charge up like I sugguest and clean everything you still have no luck, I think I'd take your battery back to where you got it and have them do a load test on it. You just may be experiencing a bad new battery. Just lately I've had 2 new batteries be bad and when we took them in they tested bad even though one was 2 months old and the other was 2 weeks old. These are things that need to be outruled before you can go much further here. Do these things and then we can go from there. Let me know if you have any questions ok. I'm keeping my fingers crossed for you that we just might find something here. Lets see if we can get ya back to that g/f of yours!....I totally agree, dealing with car probs sucks bigtime!
Right on, please do. If you still get nothing we need to take a good look at all the fuses to make absolutely sure they are all good. I'm hoping we do have a good surprize though, let me know.