It's been cooler here the last 2 days (45* in the AM).

I activate the SG2 when I turn the key on to watch voltages and temps.
The last 2 mornings, I turn the key on to let the GPs warm up and I notice
my Ficm Main Voltage drops from 34v to 3v in about 5 seconds, so I don't
bother to turn the key. Other volts are 11.7 to 12, including analog volt meter.
I cycle the key and FMP goes to 48v and I start instantly no issue.
During drives FMP is 48.5 to 49.5, I've never seen it waver.

So, this AM, with the FMP at 3v, I turned the key and no start.
I cycled the key once, same thing, then on the next attempt FMP went to
48v and truck started instantly...

So, is this the FICM, or a lame power relay/feed to the FICM?

I am driving from FL to NC tomorrow, so a FICM replacement from Ed
isn't gonna happen before the trip.. but Atlas 40 from Ed would be
fine with me - I just don't want to do it before needed..

Thanks

EDIT:
no engine bay work in the last few months, but it just occurred to me
we had LOTS of rain over the weekend, although I did drive in Sunday
without issue..

 

Couldn't hurt to swap out the relay.

Seems like a weird situation that cycling the key gets the voltages up.

Josh

 

I never cycled my key when mine was doing that some what.

And, like you found, NOT turning the key to start until 48v. works best.

I went for months with dropping main power voltage until I could have the truck down while the FICM went to Ed.

The lowest mine got was 30v and in 10 seconds or so, reached 48v then I started.

AND, the rest of the day it remained at 48v on KOEO.

Ed repaired my FICM and it has stayed where it belongs ever since.

This situation is why I like the scangauge II over my Torque APP or an APP like DashBoss. Those 2 APPs take too long to sync with the PCM to catch those readings at first KOEO.

And it is why I always tell folks to test FICM with a second person to turn the key on. Takes longer than 10 seconds to turn the key, crawl up a step ladder and carefully put the probes on the FICM.

Need to get your FICM fixed.

I have a video of what mine was doing if you would like to see it.

 

Thanks for that info.
I am wanting the Atlas 40 from Ed, my off-the-line turbo lag is huge,
I just didn't want to "hope" this was the FICM vs. something external
to the FICM.

At first, I thought the SG2 was confused, hence I tried to start - once.
Don't need to buy new injectors too..

Oddly, mine FALLS from 36 or so, to 30, 24, 18, etc. until it stays about 3v
during about 5 seconds or so. I changed the SG2 to "fast refresh" a few weeks ago.

Cheers.

 

When my FICM started to go it showed 48+ at all times except after my truck sat at work it would fall to 43-44 volts about 3-4inutes after starting and only held that voltage for a few seconds.

I went ahead and did the exchange program with ED, but certainly FICM's seem to do weird stuff when they go.

Josh

 

I wonder if it's dependant on the adapter used for Torque? As soon as I plug mine in the Droid connects with it and has a CAN BUS error or can't comm with the ECU error then as soon as I go KOEO the rest of the readings pop up. I'm going to have to time it next time -- I haven't played with Torque as much as many of you have...

 

It depends on what firmware and app revision for DashBoss in regards to connection time.

The newest beta version is pretty quick.

Josh

 

I thought of another test to try (appologies for getting off topic), since I wanted to be sure that the OBDII plug was hot w/o KO. I went out to the truck and didn't even take my keys. Started Torque, went to adapter Status and with one hand on the Adapter, in position but not seated, I watched the Torque Bluetooth connection to adapter. It was almost instantaneous from pushing the plug in to the status changing to "connected" on Torque. So I know at least on my truck the OBDII port is always hot.

I was pretty sure it would work that way and since watching the FICM voltage at Start Up is key, I'd be out buying a scangauge if it didn't work...

 

Just wanted to link to the solution in case somebody stumbles upon this in the future)

Had FICM upgraded by Ed and problem remained (but I love the atlas40)

Replaced the FICM Power Relay and it fixed this problem.

https://www.ford-trucks.com/forums/1...ng-solved.html

 

$33 for a regular Bosch relay?

Josh

 

It was $11 if i was wholesale.
Not sure it's a "regular" relay, it says 70 amps

 

Bosch relays are dirt cheap. 30,40 and 70 and 75 are very common.

Josh

 

I wouldn't worry about the price this time. Sometimes you have to bite the bullet when you want to get 'er done!

Peace of mind is worth $33.00 to me.

 

Yeah, I'm not sure if it's because I'm older or having a 44 gallon fuel tank and an Excursion has made $33 dollars seem cheap.

Heck, I spent $75 for a case of Mercon SP two weeks ago, and bought 2 gallons of Rotella T6 with a $5/gal rebate last week. Each time I stopped at those stores, I experienced the need for this relay! when I tried to leave.

Having FTE to work out these issues has saved me SOOOO much $$$ I can't help but be thankful to all the folks that share their knowledge on FTE.

Gonna run some tests on the old relay before I cut it open to see inside.
Didn't cut open my Oil Cooler so this is the how I can contribute..

 

At $33, still a relatively inexpensive repair. You would have dropped over a hundred just rolling it in the door at the dealership. I think you're money ahead.