Gary, Thanks for your ideas. I think we will take it to another dealer. The only issues are that the check engine light is on and then sometimes the wrench light comes on. I spent 2 hours on the phone with Ford today to no satisfaction. They basically said "I am sorry" 40 times and that "this is cutting edge technology". I asked over and over for their help and they said there is nothing they can do.
The car still runs. The only thing is that it sometimes hesitates when starting out.
Any ideas would be very appreciated.
I will be back on the phone again tomorrow with the Ford people. I cannot see having this much of an expense on an 08' model. It is just absurd!

 

Can you take the vehicle to an autoparts store have the the codes read? Or even purchase a code reader (a scanguage II will do this) from them and they can show you how to use it? The codes will (should) pinpoint the area(s) of problem. With this information posted here, you should be able to receive more specific help.

The bad news for you is the 120,000 miles on your vehicle. You hybrid equipment may no longer be covered (8 year-100,000 miles warranty for MOST states).

 

I gather you don't live in a CARB state. The warranty on the battery is 150K / 10 years in those states, 100K/8 years in other states.

And yes, definitely get a second opinion.

 

Replaced our 12v battery with a yellow-top Optima. It fits the space just fine, the posts are the only thing that makes it taller than the original Group 96R battery.

 

I have my original 12v battery purchased with the vehicle (used) in 2006. My mileage has decreased from around 34 to 28. Could the 12v battery be the culprit here? I realize it only supplies small amounts of current for accessories, etc, but I read at the beginning of this thread that they thought the mileage may be affected due to the HV battery needing to recharge the 12v battery more often.
No check - indicators are showing up, but not sure if the battery is being monitored that closely.

 

I don't think the 12v battery could be the cause of your mpg loss. I have an '06 FEH, delivered in Dec '05 & manufactured in May '05. So I think the 12v battery is probably about 6 years old right now. I have seen no problems yet. The 12v battery does little more than float the 12v system and so never sees the stress that a 12v battery in a regular car sees.

If it did start going bad the current it would draw would not cause the drop in mileage that you're seeing. You have something else going on.

Since the 12v battery is needed to close a starting relay to get the ICE running, when it fails completely you'll know it. Remember that the power to spin the ICE comes from the Traction battery. However a battery that has as little load on it as this one does will have to be really gone to get to the point where it can't pull in a relay.

 

Thanks Bill, just saved me having to buy a new battery.
Are there any warning or check indicators that come on when the 12v battery needs replaced?

 

In the aircraft world they have a thing you can buy called a Volticator™. It plugs into a cigarette lighter plugin. It'll tell you much about your battery and about the system when running. If you're concerned about the age of the battery one of these might be a good investment.

In normal service a battery "flexes" some with each charge & discharge cycle. Recall it has to put out some 800 amps for a short period. This one doesn't. Each time it flexes a tiny bit of material spalls off the plate surface and falls to the bottom. When enough fills the bottom to touch plates and short things, the battery starts to die.

It'll be interesting to see just how far these batteries will go since they have so little stress.

 

If it's the original battery there should be an optical indicator on top of the battery. Not sure how it works, but mine still shows "green".

 

I suspect your first warning will be when it doesn't have the juice to pull in the relay to start the engine... and that's pretty far gone.

The little green eye is a specific gravity thing. There is a float ball in there and as the battery weakens it sinks with lower specific gravity and changes the color of the eye.

It'll likely stay green until the battery is on its last legs. It only reflects the condition of one of 6 cells in the battery.