I Have a 2005 Ford F250 6.0 PowerStroke diesel with 130k miles on it. The battery light has intermittently starting coming on. I recently bought a ScanGauge II with X-Gauges and ran a scan. Here are the results at idle:

Engine Oil Temp (EOT)=168
Coolant Temp (FWT)=173
Injection Control Pressure (ICP)=580
Injection Control Pressure (ICP)%=21.8
Injection Control Volts (ICV)=0.81
FICM Main Power (FMP)=48.0
FICM Logic Power Volts (FLP)=11.5
FICM Vehicle Power (FVP)=11.5
Volt (VLT) =11.8

When driving, at ~1,800 RPMs the VLT fluctuates between 11.6-11.9. My batteries are 4-5 years old, but I had them load tested in the shop about a year ago and they were fine. I'm wondering if the alternator (still the original) is starting to fail?

Also, I'm new to the ScanGauge II device, but looking at many of my readings I see mine are under the recommended specs at idle or operating range. For example, at idle EOT should be 190, but mine is 168. ICP should be 625.5, but mine is 580. ICV should be 1.0, but mine is 0.81. Are these numbers indicative of a problem?

If you need more info, please let me know.

Thanks!

 

Your numbers look ok to me all but ficm lp and vp , is this truck fully warmed up or values taken cold? when you do your test for alt make sure fully warm and turn everything on + head lights, fan, radio, wipers ETC. nothing below 13.3/ 13.2 . Ideally a good charging system see's 13.8/14. but on cold start your glo plugs are on for 10/15 seconds .

 

Everything looks great but voltage. Like said by above, 11.8 is not good. And if that was full warmed up, change the thermostat as well, should be closer to 192... how's your mileage... the truck will thank you and so will your wallet. Better mileage with warmer temps.

 

Those were cold values. Also, I didn't have anything other than the radio (and the truck) on - no head lights, fan, wipers, etc.

 

Mileage currently sucks and has always sucked, but then I attributed that to it simply being a diesel. Using the trucks electronic fuel economy readout on the instrument panel, I average 12 MPG on city streets, can bump up to ~14 at 65 MPH on a highway. Also, when you say "should be closer to 192" are you referring to EOT, or coolant temp?

 

A good working thermostat

 

A good working thermostat should be coolant temp near 192, not 168. Anything under 185 and it's throwing excess fuel to get the truck warmed up above 185 and why your mileage is in the toilet. Ideally you want 210, diesels love heat.

 

I just went for a drive and here are my readings while warmed up and doing 30-50 mph:
Engine Oil Temp (EOT)=190
Coolant Temp (FWT)=191
FICM Main Power (FMP)=48.0
FICM Logic Power Volts (FLP)=11.5
FICM Vehicle Power (FVP)=11.5
Volt (VLT) =11.6 to 11.7

 

You definitely have a bad alternator. I would question your batteries as well since even with a bad alternator I would think you would still see 12.5 or so after glowplus turn off.

 

Bad alternator, don't wait on it either, that low voltage will kill the FICM if not careful. The progression is usually bad batteries followed by a bad alt and dead FICM... YOUR next. Get the batteries check independently and unhooked from the truck, same for the alt.

Use Advance Auto, buy a new 2005 alt and make sure it's the 140 amp model. By on line and use coupon code TRT30, save $50. Do in store pick up 30 minutes later. Clean your negative ground on the frame as well for better voltage flow.

Use the kick stand under the belt tensioner and be done with the job in 15 minutes.

 

I've watched a few videos on replacing the alternator and it looks super easy (1 beer job, at most). My truck is still stock, and outside my wife pulling our two-horse trailer a few times per month, there are no additional electrical draws (no light bars, no super stereo system, etc.). Any recommendation on batteries? And is this alternator you would recommend?

 

I use the 1000 CCA Gold they sell at Advance, they carry a 5 year warranty, no questions asked, run $165 each. I can get the exact name in the morning for you.

Keep the cart to $150 or less, use that code and just check out a couple three times. Buy a battery, use the code. Buy again, use the code again. Just keep the cart to as close to $150 as you can... that puts those batteries at about $115 before tax each... great deal.

That's the one. Batteries should be 12.6-12.8 all the time, less than that indicates a problem. It will dip to 11.6 during the glow plug cycle, after that like Bradford said, 13.2 and up for a heath charging system.

Good warranty on that alt also.

 

Yes that's too Low on Voltage, your other side of the FICM Board is taking a hit at 11.6/11.7 your VP and LP should be
LP=KOEO-12.0 low- 13.5 high- 13.5
VP= KOEO- 12.0 low- 14.0 high- 14.5
Get the Alternator in, charge the Battery's and see if LP VP comes back up If not then a FICM will be in Order too. That's a great deal Watson posted , I like a store I can run ( walk ) into and exchange a product, Napa 140 amp Power Premium Plus.

 

I would check the ppositive battery cable for corrosion, too. And, I agree, get the batteries, too, while it's still summer. No need to wait until it won't crank on a cold morning.

 

Just checked the two batteries I have in the truck, they are Fleet Farm's brand bought June of 2011. They are 1040CA/880CCA/65BCI. I wonder if the 880CCA is why my truck struggled to turn over and start on some of the below zero days here in Wisconsin this past winter. Doesn't seem like any of the big box retailers carry a 1,000+ CCA rated battery (at least not that I can see on their websites).