FICM voltage decreases under load - Ford Powerstroke Diesel Forum
Powerstroke.org is the premier Diesel Truck Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 08-20-2012, 06:39 PM
Member
 

Join Date: Jul 2009
Posts: 80
Thanks: 1
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
FICM voltage decreases under load

Key on 48.5 vdc.
Cranking 48.5 vdc.
Light throttle 48 vdc.
As load increases voltage drops. I have seen a low of 32 vdc while towing 11k up a long grade in 90 degree heat. Is this normal?? Voltage as seen on my CTS

Last edited by motorhead440; 08-20-2012 at 06:41 PM. Reason: Additional data point
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old 08-20-2012, 07:03 PM
Premium Member
 

Join Date: Jan 2012
Location: Gulf Coast
Posts: 5,201
Thanks: 1
Thanked 1 Time in 1 Post
Feedback Score: 1 reviews
Absolutely, not. Ficmrepair.com, and load test your batteries.

Sent from my phone that somebody didn't help me get.
Reply With Quote Quick reply to this message
  #3  
Old 08-21-2012, 05:43 PM
Member
 

Join Date: Jul 2009
Posts: 80
Thanks: 1
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Honestly , beyond watching the voltage fall on my CTS, I am seeing no negative effects. Truck runs great , quick starts, a minute or two of stiction in the cold months. It gets great mpg, 15.5 city, 19 - 21 hwy and 12 - 14 towing 8k boat 10 k camper.

I'm concerned if I touch it, well , things may change.

I have not found anyone describing a similar FICM behavior.

Thoughts ?

Last edited by motorhead440; 08-21-2012 at 05:45 PM. Reason: spelling
Reply With Quote Quick reply to this message
  #4  
Old 08-21-2012, 05:50 PM
The Silent Service

 

Join Date: Dec 2010
Posts: 5,210
Thanks: 0
Thanked 30 Times in 8 Posts
Feedback Score: 0 reviews
If you are seeing voltage drop, you're risking your injectors by not correcting the issue.

Since its when its running, under engine load, I would have your alternator and your batteries load tested and replaced before touching the FICM.

You have a few options when you do, have FICMrepair.com rebuild it, get a remaned unit (both of which will fail again), or step up to the power supply and heat sink from BPD and fit it to your current logic board (and not worry about another failure).
Reply With Quote Quick reply to this message
  #5  
Old 08-21-2012, 06:23 PM
Super Moderator


 

Join Date: Mar 2008
Location: Abingdon, Md.
Posts: 11,983
Thanks: 4
Thanked 31 Times in 16 Posts
Feedback Score: 3 reviews
What Ben said.
Reply With Quote Quick reply to this message
  #6  
Old 08-21-2012, 06:25 PM
Member
 

Join Date: Jul 2009
Posts: 80
Thanks: 1
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Hmm good points. Batteries are brand new ,less than a month old. Original alternator 134k miles. Maybe I should start there.

Thanks
Reply With Quote Quick reply to this message
  #7  
Old 08-21-2012, 06:29 PM
Premium Member
 

Join Date: Feb 2012
Posts: 987
Thanks: 5
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
Send it to Ed at FICMrepair.com, I just did the same thing today.

If you end up taking it out I found it was easiest to remove the whole air filter assembly and drop the coolant reservoir in the spot where the air filter was. I realize this isn't necessary but it added a lot more working room and I didn't have to drain any coolant.
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Ford Powerstroke Diesel Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -8. The time now is 03:47 AM.


Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.1
Garage Plus, Vendor Tools vBulletin Plugins by Drive Thru Online, Inc.

vB.Sponsors