Four wheel drive not engaging, light not coming on

Hi,

It's odd this happened after you cleaned the neg terminal. You mentioned you reseated the ground cables in the terminal, which leads me to believe it is a replacement clamp. Are you certain that everything is making contact and nothing was pulled loose?

If everything is tight and connected, the next thing I need you to check is the fuse for the 4wd control module. It is located in the central junction box at the end of the dash. See pic 3. If the fuse is good, confirm there is power to it.

Here are a few links to help. Also, the attached pics will help with location.

https://www.2carpros.com/articles/how-a-car-fuse-works

https://www.2carpros.com/articles/how-to-check-a-car-fuse

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

https://www.2carpros.com/articles/how-to-use-a-voltmeter

https://www.2carpros.com/articles/how-to-check-wiring

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Let me know what you find.
Joe

Hi and thanks for the reply.

I checked all of the fuses today, not by pulling them out. I used a fluke meter set to ohms and touched the contacts at the top of each fuse. The bigger ones I did pull out and examine.
With the truck running, I turned the selector knob to 4H and listened to the transfer case control module to see if I heard and clicking. None. No matter what I did. So, either it is bad or it is not getting power. Next I backed up and went to the selector switch itself. I did not have a schematic so I was just testing continuity with the switch in different positions. No matter what position I had the switch in, the continuity was the same. I would have thought it would change when I turn the switch. I feel like that might be it, so I am considering buying it first. It is only about $30.00.
I will go back and see if I can find out if it is getting power to the switch first, though I wish I had a schematic for this system. I will post back what I find.Thanks for the help.

Hi,

I attached the schematic for the 4wd system. I had to break the picture down so you could read it. I did overlap the pictures so you can follow them.

Let me know if this helps or what you find.

Take care,
Joe

Okay, my brother in law just helped me do some testing. We tested the switch plug with the truck running and the lights on and then off. It is getting power to the switch. We took the switch out and tested the ohms while turning it to the different positions. The ohms changed at each position. Since the ohms change, I am assuming it is working.
So, I now think it is the control module, I pulled it out to get the number off of it.

What do you think?

Hi,

Everything you did sounds correct. One last test I would do before replacing the actuator is to confirm there is power to it. In other words, disconnect the connector at the actuator and confirm there is power there. If there is, it sounds like the actuator.

Just from experience, I have found to confirm power is making it the entire way. LOL

It sounds like you already removed it. Place it on the ground and plug it in to see if anything happens when you shift. Also, here are directions in case you need them for removal and replacement. The attached pics correlate with the directions.

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TRANSFER CASE SHIFT MOTOR
Transfer Case Shift Motor

Removal and Installation
1. Raise and support the vehicle.


pic 1


2. Disconnect the transfer case harness connector.


pic 2


3. Remove the two bolts retaining the harness to the motor assembly and connector.


pic 3


4. Remove the rear bolt.


pic 4


5. Remove the remaining front bolt and the motor assembly and connector. Note the position of the triangular shaft extending out of the transfer case cover.

6. CAUTION: Do not gouge or nick the aluminum surface.

Clean the mating surfaces of the motor and the transfer case cover.

7. CAUTION: Install the motor within 15 minutes of applying the silicone sealant or it will be necessary to apply new sealant. If possible, allow one hour before filling the transfer case with lubricant to allow the silicone sealant to cure.

To install, reverse the removal procedure.
- Apply a thin coat of Ultra Silicone Sealant F7TZ-19554-AA or equivalent to the motor housing base.

________________________________________

Let me know what you find or if you have other questions.

Take care,
Joe

I'm sorry, I was talking about the control module that is behind the passenger's side kick panel. Ford part # 1L54-7H417-AC (see picture).

We did confirm there was power going to the control module so we are assuming it is the issue.

Should I test the transfer case shift motor too?

Hi,

Not a problem. Honestly, I would check for power at the shift actuator motor as well. If there is no power, then you are most likely correct. I only suggest this because the motor itself could have failed.

Let me know what you find.

Joe

If the motor is getting power, does that mean that is the problem?

Hi,

If the motor is getting power and doesn't respond, the motor is most likely bad.

Let me know.

Joe

No power at the motor. At this point I am assuming it is the module. I think I can get one from a junk yard for $50.00 or I can buy a new one from Amazon for $158.00. Thinking I may try the $50.00 one first. What do you think?

I bought the module from the junk yard, it worked. The first time I started it up, I saw the lights on the dash light up and go off again. I switched it into 4wd and it worked. so, I am fixed at this point. I want to thank you for your help.
Thank you and God bless.

You are very welcome. I'm glad to hear it's working again. I'm glad you confirmed it wasn't the motor. Good job!!!

Please feel free to come back anytime you need help. We'll be here.

Take care,
Joe

Are you interested in selling the vehicle?

Hi,

I don't think it is something that is for sale.