[DEESLVRGN]

Since it started getting cold, around 20*, when I start my truck in the morning, it idles rough and FICM reads about 43-44v according to my insight. Is this normal or does it sound like it's on it's way out. Also, I just took a trip to upstate NY, while driving up there 15-20* outside air temp, my EOT/ECT delta was as high as 17*, once I got back to NC in the warm, it was back to 4-5* delta.

Any feedback is greatly appreciated. Thanks.

Truck now has 167k miles.

 

[Rhys05]

I would get it rebuilt, they say less than 45V at any time = rebuild time. Send it to FICMRepair.com, Ed will take care of you!

 

[DEESLVRGN]

Problem is I can't be without my truck, only vehicle at the moment

 

[Rhys05]

If you check out the website, it looks like they might have an exchange program where you can order one (probably paying a core charge) and when it gets to you you install it and send your old one to them.. I don't know, I sent mine to them and it took about a week (including shipping, I didn't do the overnight thing).

 

[dfuzz78]

Not normal. Your FICM is toast. It shouldn't drop below 48 volts anytime.

 

[DEESLVRGN]

Thanks, I'll check out the site, but doesn't it have to be programmed for specific trucks or am I thinking of something else?

 

[novemberdelta]

No it doesn't have to be programmed to your truck.

 

[DEESLVRGN]

Replaced the FICM over the weekend, plugged it in started right up. It wont get more than 47.5V according to my edge . I should've checked before, but i decided to check for codes and came up with p0611. would the code stay there if I put a good FICM in? or would this reman one cause it?

 

[Brieldo]

Try resetting the trouble codes and see what you get. That code may be lingering from your previous FICM.

 

[Coach73]

What about the input voltage? I've noticed that after the glow plugs have cycled my voltage is down to 10.5 - 11, truck starts fine and FICM voltage is always above 48 v. I've been thinking about new batts but hate to throw $300 at it. I load tested both batteries and they passed. Coach

 

[DEESLVRGN]

I didn't load test them, but with a volt meter KOEO, 12.3V both, thats with the hood light on..... I just gotta get the patience to take em out and get em tested, even with the previous FICM, after it warmed up it would stay at 48V

 

[skanj0]

I didn't load test them, but with a volt meter KOEO, 12.3V both, thats with the hood light on..... I just gotta get the patience to take em out and get em tested, even with the previous FICM, after it warmed up it would stay at 48V

The power supply side of the FICM merely takes the available input voltage (BATTV) and multiplies it by a factor of 4. When I go to start my truck (cranking and glow plugs on) my BATTV is 11.7 to 11.9 depending upon ambient engine temperature. This produces an FICM_M of 46.8V to 47.6V. As soon as the engine starts the BATTV increases to 12.6 to 12.8 while the glow plugs remain on. This keeps the FICM_M at 47.5 to 48.5 (~48 being the maximum output of a stock FICM). Once the glow plugs cycle off (about 60 to 90 secs) then BATTV jumps to 13.8 to 14.2. FICM_M stays between 47.5 and 48.5.

Until my FICM half shell was replaced recently, my FICM_M would be as low as 27 to 28 just after startup, and would gradually rise with increase in ECT/EOT, until ECT/EOT reached 145F, when FICM_M would jump to 45 to 48.5.

Hope this helps.

 

[DEESLVRGN]

my battery with the truck running gradually climbs to 13.3-13.4 fairly quickly. So I guess running around 47-47.5V is alright

 

[PGreenSVT]

Since it started getting cold, around 20*, when I start my truck in the morning, it idles rough and FICM reads about 43-44v according to my insight. Is this normal or does it sound like it's on it's way out. Also, I just took a trip to upstate NY, while driving up there 15-20* outside air temp, my EOT/ECT delta was as high as 17*, once I got back to NC in the warm, it was back to 4-5* delta.

Any feedback is greatly appreciated. Thanks.

Truck now has 167k miles.

The only way this make sense to me is if the ECT was low when in the 15*-20* weather. Your ECT should be at a minimum 190*-192*. If it is running in the 180's or lower your thermostat should be replaced.

What were the values for the ECT/EOT when you saw the 17* delta?

 

[f350powerstroke]

got my ficm replaced via warranty a month ago.

 

[DEESLVRGN]

I run 160 to 175

 

[JasonY]

Yeah thats low. Need a new t-stat. Mine did the same thing when the weather got cold.

I run 188-190 now and EOT hangs out around 193-195.

Jason

 

[DEESLVRGN]

I have done plenty of T-Stat changes in 5.0l, is it a simple job in these as well?

 

[Coach73]

I just did mine in the driveway, about 0* outside. I pulled the air filter assy it gave me a lot more room, took maybe 45 minutes but that included the time I fought it before I took out the air filter, lost about 1 1/2 gallons of coolant. Good luck. Coach