4x4 turns itself off 2003 Ranger - Ranger-Forums - The Ultimate Ford Ranger Resource

Drivetrain Tech General discussion of drivetrain for the Ford Ranger.

LinkBack Thread Tools Search this Thread
Old 08-14-2016
klc317's Avatar
Thread Starter
Join Date: Sep 2006
Location: Cincinnati, OH
Posts: 950
4x4 turns itself off 2003 Ranger

I have a 2003 Ranger XLT 4x4, with the rotary dial 4x4 switch on the dash. It doesn't get driven all that much, just under 70k miles. Last winter I used it in the snow and noticed that when driving around in 4-high it would occasionally just come out of 4x4, light on dash would go out. If you'd turn it back to 2wd and back on to 4-high a few times it would work again for awhile, but then just turn off again. Theres no flashing 4x4 light or anything, just seemed kinda random. Otherwise everything was normal.

I would like to get some ideas of what to diagnose before this winter. I was thinking maybe the shift motor may have some dirty contacts due to lack of use??

It is very well maintained and quite clean underneath, no rust problems or excessive corrosion on anything.

Thanks for some ideas!
Reply With Quote
Old 08-14-2016
RF Veteran
iTrader: (1)
Join Date: Jan 2014
Location: Vancouver, BC
Posts: 7,281
The 4WD module(TCCM) sends voltage to the 4WD switch when key is on.
In the 4WD switch are 3 resistors, one for each setting, OFF, 4hi, 4Low.
The voltage the 4WD module gets back from the switch, after it passes thru the 1 resistor, tells it what the switch position is.

This is similar to cruise control controls, each button uses a different resistor so cruise control "brain" can tell what button was pushed by the voltage change.

Google: 2003 Ranger Transfer Case Control Module

If the 4hi actually changes back to 2WD then problem could be in the switch or the 4WD module, misreading voltage from 4WD switch.
If the light goes out then motor has to be moving to disconnect it.
The 4WD lights are simple contacts in the motor housing, when motor moves the 4 contact "switches" located on a wheel in the motor housing open and close, this tells the 4WD module when the motor is in position for 2WD, 4hi, 4low, and these contacts also power the 4WD dash lights.

Flashing light means motor didn't respond to 4WD module, or didn't move far enough, which is often just a fuse issue.

Here is diagram for '01 Ranger 4WD system, its the same as '03, fuse #'s may be different, but I don't think that is your issue.
Attached Files
File Type: pdf 01 4.0l 4wd.pdf (54.1 KB, 47 views)

Last edited by RonD; 08-14-2016 at 10:12 AM.
Reply With Quote
Old 08-14-2016
klc317's Avatar
Thread Starter
Join Date: Sep 2006
Location: Cincinnati, OH
Posts: 950
Wow, very helpful info. Thanks a bunch RonD! I'll go check some stuff.
Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
Ranger keeps flooding itself while running then clears up again. fatalerror General Ford Ranger Discussion 2 07-02-2010 08:59 PM
Does this balljoint look like it's unpressing itself? Prerunner-Ranger Suspension Tech 26 04-09-2009 11:52 AM
Seatbelt unbuckling itself korey89 Interior Semi-Tech 9 11-04-2008 07:39 PM
Alarm Diode / Goes off by itself nemo General Technical & Electrical 3 08-20-2004 08:44 PM

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 Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT -6. The time now is 05:25 AM.