03 7.3 won't hold a charge, new battery's and alt. - Ford Powerstroke Diesel Forum
Please Visit our Site Sponsors
911 Urgent Situations Emergency Forum , Need Help Fast ? Post Here ! Urgent Topics Only

Powerstroke.org is the premier Diesel Truck Forum on the internet. Registered Users do not see the above ads.
LinkBack Thread Tools Display Modes
Old 03-08-2014, 02:34 PM
Powerstroke.org Rookie

Join Date: Aug 2013
Posts: 1
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
03 7.3 won't hold a charge, new battery's and alt.

Need help ASAP
Reply With Quote Quick reply to this message
Sponsored Links
Old 03-09-2014, 07:01 AM
Compression Ignition Addict

Join Date: Dec 2007
Posts: 5,456
Thanks: 4
Thanked 143 Times in 136 Posts
Feedback Score: 3 reviews
That's 2 of 3 components to this though...

If the Batteries are all they should be and the Alternator is doing its job, then you have sufficient reserve power and it gets replenished as it should. So, all that's left is that you have a Drain. All the power that batteries have is being siphoned-off by something as the truck sits. It's called a Parasitic Draw and you have a puzzle to solve

For this there is the Scientific Method, if you have the tools & understanding you do it this way ->

In that vid he talks about a 50mA max and how some vehicles require 1/2hr to settle-down after the last thing gets activated. Our trucks can take that long, and actually draw a little more than 50mA when finally ay rest.

The next way is a Caveman Method if you don't have those tools and just a simple "process of elimination". If you know the batteries go way down overnight, just take 1/2 the fuses out and see if it happens again.

If not, take Half of the Other half.

If so, put only 1/2 of them back.

Do this everyday, over & over, until you limit it down to the Single fuse that will stop it from happening. Then you can start to unplug stuff associated with that circuit (it's usually something like the Radio / Cluster / something like that) and check the wires that go to them...

It's a project and a puzzle
Reply With Quote Quick reply to this message
Old 03-09-2014, 07:04 AM
Compression Ignition Addict

Join Date: Jan 2010
Location: unvrhrdofit, SK
Posts: 7,011
Thanks: 0
Thanked 43 Times in 42 Posts
Feedback Score: 0 reviews
^^^ poetry

Yep, you have a drain somewhere.
Reply With Quote Quick reply to this message
Sponsored Links

Quick Reply

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:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:


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 04:32 PM.

Powered by vBulletin® Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.1
Garage Plus, Vendor Tools vBulletin Plugins by Drive Thru Online, Inc.