I just acquired a 2001 XLT and see something odd with the AWD. I'm not sure exactly how it works, and if there's even really an issue.

The car seems to drive fine, but in the process of "checking everything out" I notice the "Lock" button for the AWD does NOT seem to have any effect. (The light on the dash does not light up, and there's no noticeable change in driving like you'd feel with a true 4WD.)

What are some steps I can take to confirm everything is ok? Thanks!

 

Under what conditions are you saying that it doesn't feel like it's working? You shouldn't be trying this on dry hard pavement because good traction could lead to something breaking!

 

To be clear, I am concerned the "Lock" button does not do what the manual says - illuminate the AWD light on dash and engage the front wheel drive clutches. The fact the light does not come on makes me wonder if it's just a bulb, or if the tran isn't doing what it should when that button is pressed.

Is there anything I can do to confirm it actually is working?

 

I don't think the driveline will bind up like on a true 4WD vehicle. If I'm not mistaken, the clutches have some give to them, and while the button does "lock" in the rear differential, it's not a mechanical connection like putting a transfer case in 4wd, where it CANNOT slip when going around corners.

I think the best thing to do is to find a dirt road, and give it hell. You should have little or no wheelspin from a stop on a dirt road. I don't know what part of the country you're in, but if you have any snowy conditions nearby, the difference between 2wd and AWD should be night and day.

FWIW, the 4wd system in mine (2002 Tribute) is not working, though I haven't narrowed down exactly why...

 

The test right from the Ford manual for an 2009 is for the technician to command 100% rear wheel torque with their computer. If the vehicle resists on tight turns, it's working correctly. I know that the OP has the early version but I think Lock is equal to 100% rear wheel torque.

OP: There is no front wheel clutch, it always engaged.

I have a ScanGuage II which can be programmed to show rear wheel torque. You be surprised how much throttle it takes to get rear wheel torque to kick in after a constant speed is reached on snow. From a dead stop, it engages but drops off slowly and by the time you hit 30MPH it's off and it doesn't matter if your on dry hard pavement with good traction.

 

My 01 says auto and on on the 4x4 switch. On mine I there is a light that comes on when I switch to on. And it doesn't like to turn it does make some clunks and noise. Other then that I dont know its in.

 

i have an 06 mariner/ escape awd with the 6cyl and its automatic ... my transmission is automatic and so is the 4x4 system i hate it i don't know if its working properly or not catching up as fast as i would like it always seems behind the 8 ball and i have yet to see the 4x4 light come on... is there any aftermarket up grade to add a switch to engaged the 4x4 system from automatic to manually engaged full time 4x4 like your 01. i haven't seen a post yet of an aftermarket kit or a switch added with a description of how it was done.

 

My '02 does the unfavorable "skip and hop" dance when turning with the 4X4 engaged and with OK traction. I'm pretty certain such turns on dry pavement would indeed break something so I've never had it engaged unless absolutely required.
Granted we don't offroad much with ours, but even in deep snow I've only had to use the 4X4 a handful of times and that was only to get a little extra to get up a hill.

As noted above there is a technician test but I would suggest finding an area large enough to turn around and with loose gravel or dirt and NOT similar to dry pavement.
Turn the vehicle in a few tight circles and note the way it behaves. Duplicate the turns with the 4X4 engaged. You should immediately notice a difference in the behavior. Avoid turing extremely sharp turns with the 4X4 engaged unless traction is loose enough to allow the wheels to slip a bit. If it sort of hops around the turn, 4X4 is working.

 

It is necessary to consult the service data for the correct year, the later models are pretty much irrelevant to an 01.

If the light does not come on when the switch is in the ON position, either the bulb is out, the switch is bad, or the power is not being supplied by F4 in the CJB.

If the fault either the second or the third, the 4X4 mode will NOT be locked in the ON condition as the 4X4 relay's coil is in parallel with the bulb. If it's only a bulb problem, the the 4X4 will still be able to operate correctly, assuming no other faults, but you would simply not have the indicator light.

A quick check for fuse F4: If the airbag light comes on during bulb prove-out, the fuse is supplying power to the cluster, at least.