Tinoc573

Hi, any help really appreciated. I purchased this truck two years ago and i never tried to engage the 4x4 on it. I turn the switch to 4x4 and nothing happens. The 4x4 light on the display will not turn on and there are no engaging sounds heard. Ive checked the fuse panel, no blown fuses. any suggestions appreciated.

ford4wd08

IWE sloeniod. check the common useful links sticky at the top of the 04-08 section.

GATORB8

First thing first, I'd pull the codes.

The 4 HI light should flash with a fault, not stay unlit, could be the bulbs.

You did drive the truck for a few feet after switching the switch, right? Sometimes it takes a second to engage.

60DRB

You have the "push button" 4x4? May well be the shift motor (electrcally does what a manual floor shift lever does) on the transfer case. Those have been known to sieze up when not used with some regularity. Otherwise, read here... could be a solenoid if it's not the shift motor.

http://www.ford-trucks.com/forums/836438-everything-you-wanted-to-know-about-the-iwe-system-and-then-some.html

bloodvette

There's no feedback on the vacuum hub system, so it doesn't know if the hubs have locked or not. IF that was your problem, your dash would still say it's in 4x4, so the problem will not be your vacuum IWE solenoid. and it sounds like your not getting a fault so this points at the 4x4 switch on your dash. First thing is to verify your PCM is getting the proper signal from the four-wheel drive switch. HOWEVER I see that each setting of the switch has it's own resistor so unless it's staying in the 4x2 setting- It should indicate a fault code when switched (if it is bad) becuase a resistor value is being monitored in each setting. Very interesting. I get a kick out of how well the electronics are engineered in these things. YEa so I suspect (if you do in fact have no codes) that your 4x4 switch is staying in the 4x2 setting regardless of where you set it. At least from the PCMs perspective.

PS- Incase you didn't know, your truck has to be in neutral to go into 4LOW so try that and report back if that one works.

GATORB8

After looking at the TSB, it appears the IWE is the exception to the flashing fault:

TSB 06-8-15
05/01/06
INTERMITTENT IWE NOISE, 4WDH LIGHT AND/OR
4X4 SYSTEM INOPERATIVE, DTCS - C1979 AND
C1980 FORD:
2004-2006 F-150 LINCOLN:
2006 Mark LT ISSUE
Some 2004-2006 F-150 and 2006 Mark LT 4X4 vehicles built before 4/24/2006 may exhibit a noise in 2 wheel drive from the front Integrated Wheel Ends (IWE) and/or the 4X4 system being inoperative. The IWE solenoid may have ingested water and passed it to the IWE system causing water contamination in the vacuum portion of the system. A shorted IWE solenoid can set the codes C1979 and C1980. If either code is present, the 4WDH light will be inoperative.

bloodvette

nice find. Gatorb8 always sheds light on the problem. Gatorb8 = valuable resource.

I stand corrected on the IWE. But i still think the PCM should set a code when his "4x4 high/low indicator switch" does not match the "4 wheel drive switch" selection. But I don't know much about it, purely speculation. I am still gonna put my money on the 4x4 switch on his dash.

Tinoc573

Hey guys thanks alot for all the input. I went ahead and took off the shift motor(Selenoid?) located on the driver side of the tran. and moved it around a little. I then went and hit the switch and i heard it move. I then re-installed and its seems to engage now. I'll give it a test run soon. Thank all of you for your input. This site is awesome!!!!!!!!!

B21

I know this sounds shade tree, but if you ever have the problem again, get a hammer and give the solenoid a tap or two. I had a guy suggest that to me and it works every time my 4x4 wont engage (same problem as yours).

kravenf150s

It worked for me! i was driving home and decided to "check my 4 WD" No light and nothing. Read the forums, and i started with the easiest. Slight tapping of the solenoid on the trans. It worked!