'03 Taurus won't start then does?

[jfmajor60]

I've got an '03 Taurus with 45,000 mile on it, a problem has developed where i go out every once in a while and there is seemingly no electrical power whatsoever, it won't start cant even get the dome light or the horn to work, after leaving it set for about 15 min its starts without any problem, I had the battery tested and its good, anyone have any ideas as to what is going on?

[shorod]

Welcome to the forum!

Have you made sure the battery cables are clean and tight? Not just by looking at them, but actually pull them from the battery and make sure there is no build-up of corrosion between the terminal and battery.

Since it's a 2003, I would doubt that it has temporary (bolt-on) battery cable ends, but if it does, throw them away and install molded cables by application.

Do the headlights work if you turn them on when it seems there is no battery power? What is the battery voltage across the terminals when the car seems to have lost all power? How about the voltage at this time between battery positive and car chassis?

Are there any environmental or operational conditions that seem to cause this problem to occur consistently (ie: after a rain, after driving the car for more than 5 miles, etc.)?

-Rod

[jfmajor60]

Ok I cleaned the cables and terminals no real build up, when it happens nothing works head lights or any thing else, it my wife's car its happened 3 times now and each time by the time I get there to look at it she has it running again so I haven't been able to measure the voltage I even drove it for a week some 700 miles and of course nothing happened, just seems to be a random thing with out any specific conditions that trigger this that I can point to

[TaurusKing]

I've had 2 weird no-start issues with a couple of Taurus I've owned. One had a battery terminal(factory)that had a hairline crack in it, caused the issue you're having,, totally random no power at all, then it would work.. I looked at the terminals, even loosened and retightened them, felt good, but actually wasn't, found it because the terminal finally broke open a bit.. second issue was the little black box that sits on your radiator, can't remember what it was called on the 87's, maybe integrated controller????, I think it's now called the ccrm, holds a bunch of relays I think,, anyway it had two ground wires coming out of it that were joined in a connector to the radiator support on top, one of them came loose in the connector, no power anywhere.. I found that one by accident, my wife calls says my car won't start, I showed up, started tugging on various wires checking them out and poof, car fired up.. can't say any of these apply in your situation, just a couple of oddities that happened to me, I think both would have been a pain for someone to diagnose