Hello,

2005 F-250, 6.0, 238,000 miles. Batteries test good on 650 amp load bank, and only a year old. Terminals clean, specific gravity in spec and electrolyte levels fine. Interstate group 65, 850 CCA. Seeing 12.5V or so volts prior to key on. Key on, engine off, dropping to 11.1V. Cranking seeing 10.5V but starting fine. After the initial delay, alternator kicks in and running 14.0. Concerned as I just replaced the FICM, and Alternator, not wanting to damage the FICM. Do I have an issue with these voltages, or just being paranoid? I have a Battery tender solar cell plugged in while parked just to be safe. My Fluke meter is reading approximately 0.3 Volts higher at both battery terminals at pretty much all times, but has not been calibrated. Any opinions recommendations appreciated.

Thanks,
Fred

 

I don't have any technical advice but I will say that your numbers are almost exactly the same as what I see on my Scangauge II on my 2005 6.0.

Same CCA in my batteries and FICM was replaced one year ago.

Starts fine and will start all throughout the day if I make several stops.

Starts fine in the morning (will plug it in if temps near or below freezing over night.

I am interested to hear what others think.

COuld this be "normal" for a 2005?

 

Very similar to what I'm seeing with 750cca batteries. While all those numbers are above minimum spec, I'm not really happy with them, I believe the cranking v could be better. It will likely be fine if you live in a southern area with mild temps but if you see much cold weather it could struggle to start and run. Here is a chart of my truck on a cold start.

 

Numbers look good, about what most see.

I see 12.75 without key on. 11.6 at key on and sometimes 10.5 at startup. Have the 230 amp N-L and it jumps to 14.2 when it starts. Just had them tested, CCA rated at 850 these are one year old and holding 825 and 819 CCA with the drivers side the weaker of the two. I also run a ctek digital charger ocassionally to desulfate the plates.

 

My numbers are about on par with the rest of you guys. I think we see all the threads about having to have the bigger alternators, Optima batteries, etc ad nasuem and think "my numbers suck" when in reality they are what a tech would consider normal. Sure I would like higher numbers too but many times you don't have to have higher numbers.

I am a firm believer in small things like making sure jr. has the fan blower and auto headlights off during a cold start, along with anything else like wipers that might have been left on. It can only help.

 

I had my 05 for ten years with Auto Zone batterys and stock alt. and never had an ficm problem. Standard parts and good maintenance is the key in my op. If you need something stronger then you have abnormal driving habits or extra equip. drawing more power. JMHO

 

Thanks for the replies, and info. I was hoping this was normal, although low in the band. You guys are great.

 

If the voltage stayed low for longer, I'd then worry. Add a ground wire from the drivers frame rail to the block, that should put your voltage a little closer to 14.3 and give the drivers battery a better input to help start the truck.

 

I posted this image in another thread, but how about if I start up a new round of people showing what they are reading from their vehicles so there is a reference for those who are getting concerned about their batteries. There are probably other details that could be added, and I could instead of making this a photo place the data into a spreadsheet like I did years ago in another forum about oil analysis, although not as extensive. The spreadsheet was updated and posted as a PDFs file so no matter what software you had you could read it. It would be a table format as not all of us have the software to show a graph of what is happening.

I think there are other details or layers of info I'd add today compared to this 5-6 years ago, and I'm up for others input. Later tonight I'll put some more thought into this. But here is the table from years back.

https://www.facebook.com/104882132926478/photos/a.232638946817462.54830.104882132926478/399115773503111/?type=3&theater
(Btw, do you guys see the image above I'm posting from Facebook? Sometimes I don't.)

Start Recovery should be changed to Engine Run, GP On and instead of Post Alt Kick In at Idle as that situation has now been documented (RustyAxlerod vid) changed to Engine Run, GP Off. In the top notes I think I would add a notation for how many hours the truck has been sitting as that will effect voltage due to surface charge, internal battery issues and KAM draw. Probably should also show how the voltage was taken as Battery Terminal/Power Port/PCM-OBD readings vary.

As with the oil analysis spreadsheets I can set it up with an Code rather then forum Handle if members want to keep info private and send it by PM. Not sure voltage readings are as concerning as what is happening inside the motor though.

 

Image looks good to me. What parameters for the spreadsheet?

 

I have seen voltages as much as .5v lower through the OBD port than at the battery posts. You need to check at the posts to determine battery health and alternator output.

 

You're going to see high 9s when the temps are well under 30 degrees without plugging in during crank. Nothing to cry or worry about.

Josh

 

I agree.

Those numbers aren't anything i would worry about. I just replaced my batteries and alternator this year and those numbers are about in line with what i see. It's when the voltage is below 12v BEFORE you activate the glow pligs or below 13V once the alternator kicks that you should be worried. I've noticed high 13s once the alternater kicks in, over 14v for about 10-20 minutes and then settles back into mid-upper 13s. In warm/hot temps outside, it settles into low 13s. This is normal for the truck and is part of the strategy to prolong battery service life.

To the OP, just keep an eye on it, but everything is good as far as i can tell.