FICM or Alternator?

[Kviper]

Started my truck this morning 17* out side probably 25 to 30* in the garage and my CTS indicated FICM at 44 to 46 V triggering the warning. The Bat V was reading mid to upper 11V. As the truck warmed up all voltages gradually came up to normal. It did the the something later in the day after sitting for two hrs or so. It never did this before hope it's just the alternator going, it is an 04 and probably the original ALT.

Thought's?

[Merc82]

Load test your batteries, but I would start looking into an ficm repair very soon.

[ZMANN]

FICM ,,,,, IMHO

what were your ALT readings at say the 2 minute mark after start ?

[southend]

Your ficm is taking a dump, and your batts look good. Ficm voltage below 45v is a sign of failure, it will only get worse over time. Your voltage is low in the beginning because the glow plugs can run up to 2 min depending on how cold it is. Your voltage cranking is important, you need to see 10+, the higher the better, and 13.3+ after the glow plugs shut off. Bad batteries kill ficms, bad alternators kill batteries, bad batteries kill alternators, eventually. Check out ficmrepair.com when the time comes. Most will say don't run a ficm with low voltage because the potential for injector damage is high. I agree, not sure that is a proven fact yet.

[najaf4life]

If you got the extra money. Get a BPD FICM.

[Kviper]

The BAT voltage very slowly came up over a period of 10-15 min of running. Once the BAT voltage got above 12V the FICM V wen't up very close to normal. The truck ran fine yesterday but I did wash it. (coincidence ?) I am taking it to the dealer tomorrow to get checked out. I have known the mechanic there for a long time and has done a lot of 6.0 work so I hope he can figure it out.

[Kviper]

So what do you guy's think? It's charging 14 V + when warmed up. FICM going bad, ALT looks good but have checked and have Batteries checked?
Also I have not read about tuner's causing FICM issue's but I do have a SuperChips tuner with the performance tune in now, I suppose I will have to put the stock tune back in?

[04cr450]

your ficm is def. going up and that needs attention quick.. I also think the batteries could also be getting weak.. Get them load tested with the batteries out of the truck(this is the only way to do this test properly, take batts out and take to autoparts store etc etc)... Then once both of these are repaired go from there... Like it was mentioned before, its in the design that the alternator does not kick on until 90 secs sometimes up to 3 mins especially if the temps are in the teens.

[southend]

I disagree with the alernator not working immediately, if that were the case, your battery voltage would continue to drop after cranking due to the glow plugs, heated mirrors, any lights, injectors, ac compressor, heated seats, radio, dash guages, or anything else you have on. The voltage does not rise quickly simply because the glow plugs are drawing ampreage, they are components that make a dead(controlled) short to create heat.

Sent from my phone that somebody didn't help me get.

[amdriven2liv]

Originally Posted by southend

I disagree with the alernator not working immediately, if that were the case, your battery voltage would continue to drop after cranking due to the glow plugs, heated mirrors, any lights, injectors, ac compressor, heated seats, radio, dash guages, or anything else you have on.

That's the reason I turn everything, in my control, off when I park for the night.