Have you tested the switch to make sure it's good?

 

It was a new switch I replaced it with. How would I go about testing it? My gut tells me it's not the switch but I could obviously be wrong.

 

Most folks get one that works from a friends truck, or get a new one (and then return it), rather tha meter it. You can also You can also check the fuses if you haven't already

 

I guess I could go get a new one. I have nobody that I could borrow a switch from. The switch was brand new when I bought it. I have checked all the fuses and they were fine.

When I turn the key the switch lights up (yellow lights also). If i turn my lights on the switch is light up there is no yellow indicator light and it will not switch out of 2wd.

I am going to see if I kept my old switch. I know it worked except for the lights.

Where is the TCCM located?

 

On some the TCCM is on the passenger side panel below the dash in the panel next to the door, but on the 99 I believe it is the drivers side kick panel. You could try the fuse on The TCCM as well.

 

Is the fuse physically on the tccm module? I know there are 2 fuses on the fuse block on the left side of the dash. I found the module and the clicking on start up is definitely coming from that module. Looks like it would be a major pain to replace lol

 

The fuse should be under the hood.

 

I don't see it listed on the diagram for the engine bay fuse block.

 

Look under ATCM to TREC

 

Not listed. Am I looking in the wrong place?

 

If that thing has a electronically controlled actuator in the front axle it may be sticking. Get under the truck and look for one then have someone put it in 4 high and see if it's that actuator binding that's causing the clicking noises.

 

Try the dashboard fuse box, fuses #14 or 24

 

I have checked them both and they are fine.

If that thing has a electronically controlled actuator in the front axle it may be sticking. Get under the truck and look for one then have someone put it in 4 high and see if it's that actuator binding that's causing the clicking noises.

I had thought of that possibility. However if I disconnect the battery and let it sit for 30 minutes the 4wd system works

 

Try taking the actuator off of transfer case,leave it plugged in,and select 4by2,4by4, should be smooth operation,do it a few times,to see if it is acting up