My '05 F250 diesel has sat inside of a garage for a month while we were on an extended trip. It was running perfectly when I parked it. I went to start it this AM and the panel indicator lights were barely visible and the starter just clicked. I checked both batteries and both are fully charged. (When my charger was put on each battery, there was no indication of any current flow and the light on the charger said both of the batteries were fully charged.)

There was some very slight corrosion on one of the battery's positive terminal. I removed the clamp and wire brushed the clamp and post to clean off any corrosion. That had no effect

Both batteries are fully charged but it is acting like the batteries are very low and almost dead.

Any ideas, suggestions, opinions would be appreciated. Thanks.

Bill

 

Check your grounds. There may be a loose or corroded connection at the engine block, or chasis.

 

It's almost always the battery terminals. Grab 'em and twist 'em. If that works, clean and tighten.

 

I have cleaned all four terminals on the battery and the problem still exists. Because of age and health problems, I'm no longer able to get under the truck to check on other connections. From under the hood, I tried to "see" were other connects were but there was too much "stuff" in the way to see other electrical connections.

I guess it get towed to the dealer to get fixed.

Bill

 

you have to disconnect the cables to tell if "both" batteries are charged. Sounds like you have a bad one. If you put your charger on with the cables on you are getting readings from both batteries.

 

Thanks for the tip. I didn't know that. I'll try it again with one battery out of the circuit.

Bill

 

batteries will still read 12-13volts even if they're dead, it's the current that counts. Pull them and have them tested at your local parts store. If they're good I'd start checking the connections and cables to your starter and so forth...

 

I did electrically isolate each battery and when the charger was placed on each one, neither one accepted a charge and the charger indicated each one was fully charged.

Do I have to leave one battery connected to the truck while I take the other one to be tested? If I remove both batteries and take them in to be tested, will that screw up the electronics of the truck? Will it cause the computer to reset? I don't want to have more and bigger electrical problems with my truck. Thanks.

Bill

 

pulling both for more than a few minutes will definitely reset the computer but I think that's the least of your problems....

 

Thanks for all of the help as my problem is now solved! I learned a lot in the process.

I decided to gamble and I disconnected only one battery and took it back to the place it was purchased as it was still under warranty. I didn't want to chance resting the computer if I took both batteries.

The one I took in was bad and got a new one to replace it. Installed the battery and my truck started on the very first try.

Bill

 

Glad to hear ya got her going again. Electrical problems can sure be foolers. You didn't mention how old the batteries were, but it would be a good idea to replace the other one now too. Maybe the store will prorate it for a good price.
Good luck!

 

now that is running take it to where you purchased the batteries and have the other one checked also

 

Excellent idea. The next time I'm in town, I run it by and have them put the meter on it. Both batteries were bought at the same time, 3 1/2 years ago. They are still under warrenty so having it check would be good thing to do.

Bill

 

as I understand it when you replace one you should replace both... glad you were able to isolate it, I hate electrical problems, they're a real PIA...