How To Trouble Shoot 4x4 Actuator

Yes it swiched back to 2wd

 

okay so the transfer case is working, that's a good sign.

remove the front actuator and solder it or order a new one for $180 from eBay

 

Thank you! I just wanted it narrowed down. Been rackin my brain about it since it started doin it again on my way to work this morning.

 

One thing that strikes me though is that you can't hear the transfer case, but you're able to switch gears.

I can't hear my transfer case, but my truck is 110% stuck in 4WD. I soldered, and that did not solve it, so I am swapping in a new Tcase tomorrow. And if that doesn't work, well, then I'll buy a new front ADD.

 

Thats the strange part with mine. I def heard my transfer case engage and disengage today. But when it engaged the 4wd light kept flashing.

This 4wd/4lo light flashing occured approx 3 times in the year and a half i owned this truck. But what happened today in the paragraph above, was a first.

The first time the 4wd/4lo light was flashing, putting dielectric grease on the three transfer case plugs solved the issue for about a year. But not this time.

Two separate issues maybe?

 

Fist thing that comes to mind is your transfer case limit switches...

On your Tcase actuator, there are two limit switches, i believe the one closest to the front is the 4Hi and the one on the back is 4Lo,
Undo both the plugs for the the Tcase switches, they will by 2 wire plugs. you cant really mess them up putting them back in because of the designated length and the design (though they seem similar, youll see why shortly)

Use a wire brush and clean around the base of the switches best you can.

I THINK its like a 21 or 22MM socket or wrench, but take the front switch out

With a Voltmeter, check for continuity on the connections while the switch is in its natural state, there shouldnt be any...
still connected with the meter, slowly depress the switch, it shouldnt take much till you here your meter beep or see that its getting continuity, debress the switch the entire range, it should be seamless in sound and NOT intermittent...
next do the same with your ohm resistance test, there should be nest to no resistance reading throughout the stroke of the switch.
If there is any discrepancy in the switches then just replace it, bi believe a dorman is like 10$ on Amazon or something, BUT there are two different style switches from the 4Hi to 4Lo, look at the plug side on the switch, there should be a tab in between the two connections, make sure you get the switch that has that...

if you go back a few pages in this thread there is a guy that posted a link to that switch i believe..


Also check your vacuum lines, your front diff and and Tcase line. I had a similar issue initially and noticed my front diff vac line was off, and it went away for a while before the issue became more consistent, but it was another issue all together... hope that helps.

report back with your findings

 

Thanks for your help. I will give this a try. It would almost be easier to figure this out if it was a constant issue. But its just so random it seems.

Do you think water penetration could be an issue. I notice when driving down the road and some water drainage during/after rain or snow melt that i drove through it may have been the times when this occured but not certain.

 

For water to effect it you’d have to be somewhat submerged for it to leak in the vent line or in the cover on the actuator if the seal is kinda shot, generally not the case though.
Crawl under, check your vent line first. Put it back on

Then check your tcase limit switches.

After those, report back with your findings

 

So I got around to swapping in the 4hi switch (reverse light switch) and now I can back and fourth from 4hi without having to turn the ignition off to get it to disengage. The light still blinks even when engaged. I tested the old 4hi switch and there is no continuity unless the switch is depressed. Tested the 4lo switch and same thing. I’m guessing both switches were bad. Ordering the 4lo switch now and thinking that should fix all the issues.

Anyone happen to know the part number for the 4lo sensor?

 

That is correct though, there shouldnt be any continuity unless depressed. If it’s better after replacing those switches then likely resistance within the switch I’m guessing

 

Interesting. I’m wondering if both switches went bad or what. I feel like I made some progress with the 4hi switch. Now if I can find the number for the 4lo sensor I may be back in business.

 

The detent type switches should only have continuity when depressed. If your old switch was ohming out fine when you tested it, it could have been intermittent or a bad connection and when you disturbed the plug it fixed it. I always put dialectic grease in any connections that could be exposed to the elements to preserve the contact life.

 

These are not vacuum lines, they are just vent lines. If they get disconnected it won't effect the short term operation unless it gets moisture in there from driving down the road. The newer systems use little DC motors, not vacuum diaphragms.

 

If anyone wants to check out my fix, go on Instagram and look up @socalexpeditions

There is a post in a circle labeled “Fix Taco 4WD.”

My transfer case was completely shot though - No sound came from it. You can see how much water was in it as well.

 

Youre right, haha, I was on a 90 hour work week and fighting a cold, not in my best state haha

got my new front actuator in this weekend and all systems go, got it all fixed!!! no flight light anymore, shift on the fly to 4x, very excited to have things working properly again!!!

Write up coming soon!!

Thanks to all who chimed in to help me get this mess sorted.

 

My issue is no longer intermittent. I have the issue as u described. When i swich to 4hi, the 4wd engages but the 4wd light keeps flashing. Nothing happens when i switch back to 2hi unless i turn the truck off and start it back up. So were these ur symptoms as well?

I havent been able to test anything yet cause of the weather but all im trying to figure out first is what location this issue is at. First i was thinking the actuator on the front diff but now im thinking it could be on the transfer case

 

Bump

 

That was my issue until I swapped in a new 4hi sensor.

Now I can switch back and fourth between 2wd and 4hi but the dash light stays blinking and I cannot get into 4lo.

I’m going to try purchasing a new 4lo sensor and see if that does the trick.

 

Where did u buy ur sensor? Is it a pretty straight forward install?

 

$10 off eBay. With spraying and cleaning the connections it took maybe 5 minutes