It's electronic, check all fuses, also check the connection to the transfer case.
Try listening to the transfer case try to engage. Mine did not engage after an engine wash. The vacuum actuater on the firewall above the distributor was not allowing vacuum to the front axle actator. You can put the truck on jackstands (all 4 wheels) and check to see if the front drive shaft engages. If so, then it's probably the vacuum actuator or the axle actuator.
My 2000 GMC jimmy had 4x4 issues. Were it would intermittently work. After numerous attempts to fix it. I found out that the control module has a metal shell which create a lot of moisture and causes corrosion which lead to the heart of the problem. Here is some home made steps I took which ended up fixing the problem.
1) check that your vacume lines are not dry and brittle, if so replace...cheap fix
2) check the vacume actuator under the battery case. If free and working its OK
3) there is a sensor on the front axle that tells the TCM if it is engaged or not . Make sure it is tightened properly. Mine wasn't.
4) the TCM on the passenger side has a connector issue. With a second person switching it in and out, wiggle the connection to see if it is loose. If so zip tie it . You will hear it engage and disengage.
5)check and clean the vacume valve on the transfer case. This. Should be part of the vacume lines.
To engage the 4x4 manually (VTM-4), you would need to be in 1st, 2nd, or reverse gear. In those gears and while stopped, you can then press the VTM-4 button, and will engage 4x4. It will only be engaged when around 18mph or lower. Above that, and it will disengage. It will re-engage when it dips down to that speed again. To turn it off, you can just press the button, or shift to a higher gear Keep in mind that even with the button off, VTM-4 will engage occasionally when there's slippage.
Give me food and I will live give me water and I will die what am I?
What is 8 divided by 2(2 plus 2)?
What is the closest us capital to Canada?
Who was Hillary Clintons running mate in the 2008 presidential elections?
Easiest way to lose lower stomach fat?
What is the prefix of done?
Baseball players with 3000 hits 300 home runs and a 300 batting average?
Which is bigger 0.3 or 0.25?
Can you get sunburned in the shade?
What are the dog days of summer?
What is the toughest academic course according to the Guinness Book of World Records 2011?
Why do so many foods "taste like chicken"?
Who invented Lincoln Logs?
How did chickenpox get its name?
What is doomscrolling?
How did the Wiffle Ball get its name?
What investment is necessary for a yield of 500 dollars per month at 6 percent interest?
When two pieces of cui or other unclassified information are posted online together?
How do you transulate happy independence day in konkani language?
How many ODD DAYS IN DECADE?
Ano ang mga salik sa pagkakaroon ng Bilinggwalismo?
Ano ang pagkakapareho ng panitikan at kasaysayan?
WHAT IS THE EXPECTATION ON THE SUBJECT NSTP AND TO THE INSTRUCTOR AND CLASSMATE?