MY 2008 6.4L will not start. When I turn the key it will try to spin the motor for about 1/2 second then click a few time and the lights go dim. RMP and Speed O needles bounce on the bottom of the gage. I have checked the batteries and cleaned the terminals with no improvement. My thanks in advance for any thoughts.

 

Gotta be batteries. Howed you check them? They should have like 12.8 or so on the volt meter. Turn on the lights and blow the horn, if lights dim it's batteries. Besides batteries are 3 year, it's just about up. One of mine shot craps last month.

 

I used a charger that said they were 95 and 100% charged. That may not have been the best way to test them. I just tried the "lights on blow the horn" and did get some minimum, very minimum dimming. I would have thought that the factory batteries would have been a 5 year battery. Got the truck new sometime in 2007, so they are close to 3 years. I guess the best bet is to take them out and do a morning run to Advance for testing?

 

Yeah, I thought they should be 5 year too, but it seems not. Good news is that they will be replaced under the bumper to bumper, at least I'm told they will. Provided of course you're still under 36K miles or have an extended. I could be wrong about the batteries but those symptoms are classic. What seems to happen is one fails and it doesn't get detected and then brings the other down with it. What does your little computer say when it runs through the checks?

 

LOL I have had the truck for about 39 months and do not have an extened warranty. After thinking about it, I have had some slow starts and I thought it was a corroded terminal. How do I get my little ecomputer to run through the checks?

 

Well lets see. Push the middle button (I think), then it will tell you to "push reset for system check" . Then the computer will cycle through a bunch of stuff and one check item will be "charging system" or something close to that. If it says "check charging system" you can almost bet the farm it's batteries.

 

You were RIGHT. I went ahead and pulled the batteries and went to Wal-Mart and bought 2 new ones and it started up. I was starting to run out of time...... We are pulling a goose with 2 Jeeps out on Friday AM for a weekend Jeep ride. If the batteries didnt fix it, I was going to surrender and call someone to come and get it hoping they could have me up and going by Friday AM. Thank you for taking the time to reply!!!

 

Thats what this forum is about, helping each other and learning together. Glad you got it going.