Question for 08 FEH owners:

Do you notice your battery fan's activity? I was told that there might be time after you turn off the car that the fan runs to cool the battery and preserve its life. I have not noticed any fan noise when he car is on (even when it's quiet like stopped at light with no engine) or after I park and get out.


I did have one wiring issue already with my driver's side reverse light- loose connection (yikes!) Is it worth having them check the wiring for the battery cooling system, or is it standard for the fan to not really run when you'll hear it(???)

I've never heard the fan in my '06 run that I know of when the key is out... The fan speed is varied specifically to make it hard to hear when you are driving and such (It slows down when you stop). Get someone to sit back there an take a listen when you are driving, and when you are stopped at an intersection in EV mode... I'll BET it actually running... you just don't notice it but there is nothing wrong with being sure.

Also.... I'm pretty sure the battery system has themostats and such and if the battery wasn't being cooled properly you'd be getting a check engine light and a message to "pull over and stop"

I've never heard our fan, but we only picked it up in September so it may not have been hot enough yet.

I frequently hear the batt fan in my 08 FEH AWD. And as TeeSter said, it's variable speed, so you have to listen closely. I can only hear it with the windows up and the radio off. Ford did their homework when they varied the fan speed with vehicle speed to made relative quiet.

I have never heard the fan running when the key is removed. Even if the battery is warm then, why waste energy to cool it, when it will cool naturally w/o energy over time. And if you do start up before it cools enough, the fan will just come on again. Works great.

I can hear my battery fan (08 FEH) on occasion when the windows are up and the radio is off but I've never heard it with the key in the off position.

I'm sure there are multiple systems in place to monitor the battery pack temperature and keep it healthy. I know the system is smart enough to monitor the door flap that controls air routing within the cooling system. I'm pretty sure there's a monitor for the fan itself. If there were a fan failure, I'm sure there would be a warning.

In the shop manual they instruct the technician to use a stethoscope to listen for the fans if it is suspected that they aren't working...

When you consider that the fan (or the A/C if it's too hot), is the life-blood of battery preservation, then the stethoscope makes sense

Since last Oct 2007 when we first got the FEH, it hasn't ever been hot enough for the battery temp to command the A/C on, or at least not that I'm aware. On the hottest day of the year so far, I happened to be driving, and watched the SGII closely for Tav and AC on indication. The fan was sufficient to keep Tav under 79F. But summer is on the way, and we will someday get as hot as it already has been this year in AZ

110F 48 hours ago, 55F and rain now; first rain since February. May use the EBH tonight. Never had that big of a change in temp in so short a time before. Tuesday leaving work Tav was 98.6F. Just recorded a fairly mediocre tank, by xgauge standards that is.

It was REALLY hot (106) last week here in SoCal. I heard a noise from the rear cargo area several time when I was stopped. I attributed the noise to the battery A/C fan. It wasn't loud, but I could hear it.

Great topic, and great timing.

It was a very cool night, 55-60 degrees last night.
My FEH was in the sun all day prior to that.
My Tav was at 87 degrees.
A/C comes on for the battery at anything above 88 degrees in my car.

I could hear the fans spinning fast. But my Tav was staying at 87 degrees for 15 minutes of drive time. I thought maybe my battery use was making heat at the exact rate the fans were dissipating it. Maybe not.
They kept spinning when I pulled into the garage and put the car in Park in EV.
So I went in back and removed the battery air filter and the air door was closed!!!
The battery pack was just recirculating the air! It was not using outside air!!!

( The fans went off the second I turned the key to off. )

SO now I don't know if something is wrong or not.
I think the car always keeps the air door closed when the power is off, but I don't know about when you are in Park, key on.
But I'm by myself so I cannot look at the door position when I am driving.
Carl, did you ever get the door position PID working on the xGauge?
It may be time for me to try that.
I still think it is wierd that my battery wasn't cooling on a 55 degree night.
Since I didn't want the A/C to kick on ( I know my freon is low... again... 3rd time... ) I was stopping in Neutral to not heat the battery past 88 degrees.

Thanks,
-John