Well, thanks to all for the suggestions. Mark - I envy you the upcoming payoff, good for you. I still have a ways to go, but I am at least in the home stretch now. The battery tender may be a good Idea, I have been considering that, and it may be a good idea. Also, I think I will have Ford do a more sophisticated load test, that seems like a really good idea at this point. I am still stuck on the fact that "something" seems to have changed. Up until 6 or 8 months ago, I never had this happen once, and if anything it seems like I do less little short trips in it now, I have another truck I usually use for that. Also, I have not checked the water level in the batteries, and will probably do that also just in case. Hey, won't I feel like an idiot if the water level is low in one or both batteries. On a high note, before I left on the above mentioned trip, I not only cleaned the Ex top to bottom, but changed the oil (rotella synthetic), and fuel filters, and had the transmission fluid changed as well. I also ran Stanadyne (hat tip to Mark) the entire way, and man, it ran beautifully!

 

Gratuitous photo of engine compartment after recent wash, dry, and Armor-all (OK, so I'm a little deranged), and after recent installation (with modifications) of Dieselsite coolant filter. Note notch out of bracket, and homemade extender to bracket. (hey look, I just hijacked my own thread

 

You are deranged...not a little...but a lot. It's nice to see those as deranged as I am! HA! Nice job on the bracket!

 

Here is what I documented on alternator control:

The HEC that controls the alternator, not the PCM.
The "I" circuit is not turned on till the GPCM timer goes off (up to 2 min depending on EOT, etc). In a single alternator setup, the voltage regulator in the alternator is turned on by the I circuit. That circuit goes to the instrument cluster and is part of what controls the battery warning light. The instrument cluster does not apply voltage to the I circuit, thus not turning on the alternator, until the glow plugs have shut off.

Good luck on your search. Please post up what you find!

 

hey 2003 excursion engine compart looks great be sure to fully charge your batts befor ford load test they will do a proper load test which is one half of the cca rating for 15 seconds also the tech can determine alt output both max amps and volts as well as starter draw when eguipment is connected also be sure to chech the connecter at rear of alt and those batt cable ends as suggested by jakebrake he is right on the money

 

Hah! This explains what happened on my Excursion the other day. I am used to my Insight CTS alarming for about 30 seconds of run time that my voltage is too low - about 11.8 or so - and then magically coming back up to 13.6-13.8. The other day, though, the truck was running for every bit of those two minutes and the alert just continued. I figured that my alternator was toast. Being mindful of the damage that I could be doing to my FICM (even though I repair them, doesn't mean I want to repair MINE again ), I shut off the truck, let it sit for a few seconds, and re-started it to see if my alternator would start to behave. Viola! I had 13.6-13.8 volts again. I haven't had the opportunity to start the truck cold again since, but bet that the glow plugs were running longer due to the colder temps we are beginning to get.

Upshot: I thought I needed a new alternator, but now see that my alternator is working as designed (and now understand why my idiot lights weren't alarming when my Insight was). Mark - you are the man. Time to add more reps!

 

Thanks Ed! I sure appreciate what you do as well.

 

Update: Checked fluid level in batteries, all good. Checked with a local dealer, and yes, they will do a free load test on batteries since I bought them there, so I will take it down later this week. They also confirmed free replacement at this point if they are bad. Meanwhile, I am letting it sit, and checking the battery voltage once or twice a day, just to see what I get. Mike

 

Well, to cut to the chase, it was the driver side battery.

More information: I also let the EX. sit all week, and checked the voltages of the batterys every day, just to see if I either had a bad cell or a voltage loss from something staying on. This showed nothing really..
10/3 12.60 volts on both
10/4 12.52 volts on both
10/5 12.43 volts on both
10/7 12.39 volts on both
10/8 12.44 volts on both (it was hotter outside than previous days)

So, I took Mark's suggestion (BISMIC) and took it to the dealer for a free load test (much more sophisticated than my own). They immediately found the drivers side battery to be bad. The passenger side did not immediately show any problems, but their load tester defaulted into a more sophisticated test that runs 1 1/2 hours once it starts. Since it was about 3:30 already, and since the mechanic said that 98% or the time that it goes into that mode the battery proves to be fine, they discontinued the test. So... they replaced the drivers side battery for nothing. I asked about replacing both batterys, which is ideal, and they said that Ford will not pay to replace the other battery if it is still good. My question is then, am I probably OK???? Again, the driver side battery will be 2 years old at the end of this month. Thoughts? My guess is that I am probably fine, but obviously when the passenger side goes eventually, I will replace both at the same time... presuming, of course, that it goes first.

Thanks to all, rep points given where I could. Thanks especially to Bismic and NCCpartsman, whom I could not yet give rep points to. I will try to spend more time on here and catch up with you guys later.

 

Thanks for posting the outcome shure does help folks out when they are searching for answers to a problem

 

6.0L Power Stroke Diesel,2003 Excursion, Possible Alternator / Voltage regulator problem ... Or not? I am not sure how to get into this dialogue about the possible alternator/Voltage regulator so her goes. First I want to communicate a caution that I picked up.. ( If you disconnect a battery cable and do not wait at least 11 seconds before reconnection it, you stand a chance of accidentally deploying the vehicle air bags.) I do not know ir this is a true concern or not but I am afraid to challenge it.
Now my problem. I am Ray, I am having a problem with the failure to start with both batteries down. When I charge the batteries with a separate charges, I can start the engine 12 times without any failure to start problems. The one thing I don't understand is when I run the engine with a total load, air conditioner both front and back and with the lights on high beam and the transmission in drive the voltage drops to 12.62 volts as measured on the batteries, with the engine at idle. (No one to help me control that big diesel to increase the rpm). Than makes me think that I have an alternator that will not handle the maximum load and that it needs replacing. If that is true, where do I get instructions on how to remove and reinstall the alternator.

 

Welcome to FTE RAY

Sounds like your alternator is Dying

Take a DVM and measure the Volts at the Alternator after truck has run at least 2 minutes

Testing at the alternator should see 14.3-13.3volts after the 2 minutes thing

 

The stock Ford alternator is marginal at best in this situation...with both front and rear A/C blowers running along with the rest of the electrical load and the engine at idle. You need to have someone fast idle the engine...2000 rpm... and then measure the voltage. My guess is that it will be somewhere around 12.9 to 13.1 volts. Look into a DCPower alternator...they will keep up with the current demands of the Excursion. Alternator R/R is not a major task...do a search and you will find lots of info. Most important thing to keep in mind is to disconnect battery grounds FIRST...and then to reconnect them LAST. Hope this helps.

 

This old thread came up and reminded me of what I intended to post about a long time back. Here have been my observations with my truck as far as battery voltage and the starting/running cycle.

Upon key on and the glow plug cycle (prior to start) the voltage on the batteries will be around 11.3 to 11.4 volts. During engine crank the voltage will drop to about 10.5 volts. Upon engine start (alternator is rotating) the voltage will rise to around 11.8 or 11.9 volts. When the glow plug timer de-energizes the glow plugs the voltage will immediately rise to 13.6 volts or so if warm and 14.2 volts if cold. The explanation for the voltage rise (11.8) on engine start would seem to be that the alternator is "self exciting" and producing a small output...even though the control circuit has not commanded an output. This might be because of residual magnetism in the alternator rotor acting on the stator coils. I have not come upon anything in a search specifically relating this to the 6.0 but I don't know how else to explain it.

 

Is the reason Ford delays the alternator output until GP has to cycled to help with GP longevity or something else?

All it takes to defeat that is to run the yellow wire to the charge post and connect the red/green to key-on.

Josh