I've got a 2008 F150 4.6L that has eaten batteries for breakfast since I bought it new in 2008. The dealer had to replace the battery when the truck had only 7 miles on the odometer. The battery was replaced twice again under warranty over the next 2 years. The dealer even dialed back all the lighting delays (auto headlights and interior light) however the problem continues. I've now replaced the battery twice since the warranty ran out. The dealer can't locate the drain. What's odd is problem tends to occur in the fall when there's a change in weather from hot to cold.
I would think the battery saver circuit would isolate any drains after a few hours, but something else is obviously continuing to use power.

One other question regarding the starter. My truck has some sort of "Crank until starts" function. When you turn the key to crank the engine the starter stays engaged until the engine starts. This is a very annoying feature given if the battery is low the starter will crank the battery dead, and there is no way to stop it even when you remove the key from the ignition switch.
What happens when you're out of gas, does the starter crank until the battery is dead only to compound the probleml?

Is there any way to have this function disabled?

thanks

 

"crank until start"? I've never heard of that. Automobile manufacturers usually tell you NOT to crank on the starter. They usually advise to crank no more than 30 seconds and then wait a minute and a half before trying again. Read your owner's manual. What does it say?

It sounds to me like you have a sticking starter relay. Dealer SHOULD realize that so I'm guessing that they don't won't to deal with fixing the problem.

You might try contacting Nick, The FMC rep, on here and ask him to find out if there is such a thing as "crank until start".

Plenty of other threads about battery problems! So go read them. Short version, most batteries today are CRAP! Even brand new ones.

One quick, SURE, way to find out if truck is draining battery is to disconnect battery immediately after turning truck off and then reconnecting when you need to use truck again. If the truck is draining the battery then the battery will be fine every time that you start the truck. If battery is dead or weak then you have a bad battery. It's that simple! Battery should hold good charge for WEEKS. Yes, you'll lose your radio settings, clock time, etc. Deal with it!

 

My truck has it, and so should yours. The feature is called "One-Touch Integrated Start" (OTIS).

Next time you go to start your truck, just bump the switch to the starter position and you'll notice it continues to start the engine. My 2011 Taurus does the same thing. It will not crank indefinitely though. And you can always halt the starter by turning the key off.

I've never had a situation where my truck didn't start normally, but the starter will time-out if the engine does not start after ten seconds.

 

Hey Scruge,

Have you tried getting a second opinion at a different Ford Dealer? I'll gladly locate one nearby for you. To do so, all I'll need is for you to PM your ZIP.

Nick

 

Since new the truck has always cranked until it started. All I have to do is just pulse the starter and it cranks until the engine fires and then disengages. Dealer told me it was by design. The engine starts within the first few seconds so its never an issue unless the battery is weak or out of gas. Then it cranks until dead.

As for the batteries, I have 2 other F150 within a year of this one with exact same batteries, their batteries have been lasting 3-4years where as this truck's battery last maybe a year. Plus its driven fewer miles it has only 68,000 and its on its 6th battery.

The problem with the drain is it comes and goes. I've monitored it over a week period of time and can't find anymore than a few 100 milliamps of draw. But when it hits, it drains the battery completely over night, the battery can be recharged and is fine for several months then all of sudden it'll be dead again.. this cycle will be repeated several times before the battery becomes unreliable.

I'd like to find out for sure about the crank until starts... This may have been the problem from the beginning.

 

Actually when the battery is low it will continue to crank even with the key removed. It freaks me out every time it happens. It cranks momentarily and then starts stressing the electrical (clicking), I can remove the key and open the hood and watch as it takes the battery to near zero. When its done there isn't enough battery juice left to charge a cell phone to make an emergency call.
Perhaps the 10 seconds limit is only functional when system is operating with proper voltage.
However I can say without a doubt the first time you experience it, its very unnerving.

 

Good to know. Never happened to me since I've not had an instance where my truck didn't start normally, nor a weak battery.

What's interesting is you've replaced the battery a few times. The first time doesn't surprise me if it was sitting at the dealer for a while. They can go months without being run, or started and quickly moved around a lot repeatedly without allowing the battery to charge.

Having the battery replaced afterwards, I assume they were actually bad and not just needing a charge.

Now it was changed twice over the next two years while under warranty, and the truck is a 2008. So if the last battery was installed four years ago, it's possible that the battery is needing replacement soon. This would be a good time to have the battery tested (free at most auto parts stores). If your truck has the smaller size 59 battery, upgrade to group size 65. All things being equal, the larger battery will have a higher reserve capacity. Don't go for the one with the highest CCA. As long as it has 650 or more, that's fine. Reserve capacity measures how much power the battery can actually store, which is far more important. No need to go crazy and buy a $200 battery though - that's overkill.

Last thing for now is I'll assume the battery is properly secured. If it is loose, it will bounce around in the box and that vibration easily kills normal car batteries.

 

Well, I learn something new everyday! I just went out and got my owner's manual and read it carefully and you're right, it does have a "computer assisted cranking system that assist in starter the engine. After releasing the key from the 4 (start) position, the engine may continue to crank for up to ten seconds or until the vehicle starts." But no mention of "One-Touch Integrated Start" (OTIS) anywhere in the manual that I can find. My truck has always started immediately (or it was immediately obvious that the battery was dead!) so I've never noticed that feature.

Still I wonder if there's a fault in Scruge's truck or it it's normal for the system to continue to crank without stopping if the battery is weak. That's sort of worrisome!

Scruge said: " the battery can be recharged and is fine for several months then all of sudden it'll be dead again.. this cycle will be repeated several times before the battery becomes unreliable."

That's the exact same kind of symptoms that I had with JC manufactured batteries from Advance Discount Auto parts. I went through five or six of them in a year in 3 different vehicles. At least two of the batteries were only a couple of weeks old, one started doing the same day that I bought it!

BTW ALL batteries sold by ADAP are made by JC regardless of the brand name on them!

Go get your battery tested! It may or may not detect a problem but it won't hurt. They did find problem when the tested mine and traded them out. But replacements from ADAP had the same problem sooner or later. I finally stopped buying batteries (and now ANYTHING!) from them. Last battery that I bought was $105 (IIRC) from Walmart. But check the price online and take the ad to them or they'll try to charge you more! Other places charging up to $169 for the same battery!

 

My truck has been fine in the summer and dies within a few days during the winter months. Without fail. Every freaking time >=(

Since it was new it has done this. I can't find a drain and it's highly annoying.

 

This may not be a solution, but you can get a trickle charger that plugs into your cigarette lighter. Doesn't address the root issue if you have an intermittent battery drain, but it's something.