Go Back   Ford Truck Enthusiasts Forums > Super Duty/Heavy Duty > Super Duty & Heavy Duty
Sign in using an external account
Register Forgot Password?


Super Duty & Heavy Duty 1999 to current Ford F250, F350, F450 and F550 Super Duty with diesel V8 and gas V8 and V10 engines SPONSORED BY:

Reply
 
 
 
 
LinkBack Thread Tools Search this Thread
  #1  
Old 01-11-2014, 05:53 PM
SDSC4X4 SDSC4X4 is offline
Senior User
 
Join Date: Dec 2012
Location: Newcastle & Gillette WY
Posts: 105
SDSC4X4 is starting off with a positive reputation.
ESOF testing: strange results

Truck is an '01 V 10/automatic.

Hubs stay engaged all the time. I've checked the hubs and lines to them with a vacuum pump (including the line to the HVAC controls), all hold vacuum indefinitely.

When I "tee" a vacuum gauge into the line going from the hub lock vacuum pulse solenoid to the hubs, I show full engine vacuum (about 16" hg) going to the hubs at all times, regardless of the dash selector switch position. (Engine running)

I also am getting 12 Volts on the center pin of the connector to the hub lock vacuum pulse relay. The schematic I've found (http://www.ford-trucks.com/forums/97...esof-help.html) shows this should be 5 Volts (VREF). Other systems powered by the VREF seem to be working fine....

I've searched many threads here, and have not seen any reference to these test results

The transfer switch shifts normally from each mode to next. All fuses are good and the ESOF relays check out fine. I replaced the vacuum hub lock solenoid in August with a new Motorcraft unit from Ford.

So, my questions: where is the 12 V coming from? Where is the 5 V (VREF) sourced? Would this voltage damage the hub lock vacuum pulse solenoid? Why the constant vacuum? In other words, I've about worn out my "bang head here sign," how do I fix this one (!) ???
*
Reply With Quote
Old 01-11-2014, 05:53 PM
 
 
 
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
ESOF Pulse Vacuum Hublock Solenoid? SDSC4X4 Super Duty & Heavy Duty 14 Today 02:07 PM
vents not working, vacuum questions LSO1123 1999 - 2003 7.3L Power Stroke Diesel 4 11-14-2011 06:33 PM
Pulse Vacuum Hublock Solenoid Problem? phydiux Offroad & 4x4 4 01-13-2011 05:57 PM
4x4 and ESOF problems BWPowersmoker02 Super Duty & Heavy Duty 5 01-02-2010 03:33 PM
Another 4wd not working question johnnybecool Super Duty & Heavy Duty 8 02-20-2007 08:52 AM


Go Back   Ford Truck Enthusiasts Forums > Super Duty/Heavy Duty > Super Duty & Heavy Duty

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not 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 On
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump


Participate In The Forums

Create new posts and participate in discussions. It's free!

Sign Up »





All times are GMT -5. The time now is 07:37 PM.


Powered by vBulletin® Version 3.8.7 AC1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Advertising - Terms of Use - Privacy Statement - Jobs
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. Ford® is a registered trademark of the Ford Motor Company.

vbulletin Admin Backup