How To Trouble Shoot 4x4 Actuator

Thank you good sir. This weekend Im planning to remove front diff actuator and do some inspection and soldering. And off to T case switches from there if need be.

 

I hope that fixes your issue as I don’t wish this stupid fucking bullshit ass nonsense on anyone!

 

Amen to that brother. I dont have the faith in the truck I once had.

 

Just a heads up for those trouble shooting engagement issues with a manual transmission. I’m not sure what years this applies to but my 14’ manual regular cab will only go into 4 Lo with the clutch, and brake pedal fully depressed. If I go to neutral and depress clutch as the instructions say to I get the flashing 4 Lo light and no engagement. Put the brake on and she engages 4 Lo smoothly. Never had an issue with on the fly 4 hi. I pulled my hair out trouble shooting mine and ran across a post that said to depress the brake as you would in an automatic.

 

I’ve never had to press the brake when engaging 4lo in my manual. I will have to try that and see if it does anything.

 

Completed the front actuator soldering today. Unfortunately it did not fix the issue.

 

Tried it. Nothing happened

 

So, ran my truck through the car wash yesterday and now both the 4x4 and 4LO lights on my dash are blinking.

Until yesterday I never had this happen before. 4x4 system has always worked fine. Also the truck is still in 2WD.

It’s a 2010 4cylinder manual if it matters.

Where should I start?


I really miss my 99 Taco and is simple 4x4 system and manual front hubs.

 

I doubt itd be the transfercase actuator itself, since you are getting 4wd... Id agree with 93yotasr5 that I would start with the limit switches. sounds to me that you can still get the funtion but not the closed loop signal that its been completed, if that makes sense.
Am i right in assuming that while in 2wd, the light is not flashing. you switch to 4hi, the light flashes, the truck (t case and ADD actuators) engage fully, but light continues to flash. ?
if thats the case, then Id for sure look at the limit switches on the Tcase actuator. Whats happening is the module is not seeing that the action is complete (4hi switch isnt sending the signal). so when you try to go back to 2hi, it cant because its hasnt completed its current request fully and has no base signal to start from if that makes sense... If all was in working order itd be the following.

4 hi to 2hi actions

4hi (add and tcase engaged) - 4x light solid
action - switched to 2 hi
module - sees limit switches in ADD and Tcase both confirm engaged (i think this is your issue that its not seeing the confirmation that the tcase is engaged )
module - disengage front ADD and Tcase wait for response to confirm disengaged location via limit switch
Add and Tcase - disengage, and confirm action via signal switches back to module that action is confirmed.


Note that the confirmation signal for the 4hi switch while in 2wd is a "no signal" signal, there is no continuity going though the switch.
the confirmation signal for the 4hi switch while in 4hi requires continuity, so if there is an issue in the switch, or extremely high resistance and corrosion then it simply will not provide a signal...

long story short.

change out the limit switch in the ADD, and go from there, thats a very cheap part to "throw" at the issue in hopes of solving it.

report back too! hahah

god speed

 

Correct that is my issue. Do u mean to change out the 2 switches on the TC? I did take those out and gave them a look and seemed fine but that doesnt mean they are fine.

And how u explained, i guess thats why it wont go to 4lo

 

Oh and at the bottom of this page, are those two limit switches one being the 4hi and the other being for 4lo?

 

A few times mine did the same thing. It seemed like it happened when the roads were wet.

This is what worked a few times before it all went to shit: There are 3 plug connectors on your transfer case(easy to get to) unplug each and add alittle dielectric grease to them. The flashing lights should go away.

Im at a fork in the road right now with my 4wd system.

 

First day I have off work I will try this!

 

Does anyone know the part number for the 4lo switch/sensor? I’ve googled it and I get conflicting part numbers with no correct picture of the part. This is the if that I am NOT looking for. I’m looking for the larger plug that goes on the transfer case closest to the driveshaft.

 

Just adding my two cents. I also had a hell of a time getting the actuator off. I couldn't see getting to the to two bolts any of the other ways described in this thread, going in from below seemed to be my only option but a regular socket was too short to reach the bolts and a deep socket was too long as my steering rack is right there. Enter SST no.1! I figured all I needed was a socket in between the regular and the deep so I cut the drive off a spare extension I had laying around and welded it on to a spare 12mm. Then I realised that was still slightly too long so I had to cut some off (left ugly in the pic). Once the bolts were loose of course the ratchet wouldn't engage but I couldn't get my fingers on to the bolt or turn the socket so enter SST no.2 (right ugly in the pic) - I cut the gear head out of an old ratchet and welded on the other end of the extension I cut up earlier. Viola! Something to get a grip of
Also found out, NAPA brake clean is awesome for getting rid of old RTV - not sure if that's been mentioned and pro tip - disconnect the electrical connector before going doing anything else because it's real hard to do once the actuator is hanging down dripping gear oil everywhere. Oh and drain your diff, it deserves a fresh fill.

 

So I’m currently dealing with the blinking 4WD and 4LO lights in my 2011 Taco. After reading through this thread and multiple others I pulled the front diff actuator, disassembled it and tested it to confirm the actuator motor worked. Motor was good to go so I soldered the connections and put it back together. Everything looked good inside so I hoped I could put it back in and have my 4WD working again.

No joy.

I am in 2 wheel drive and can not get the 4 wheel drive to engage in 4H or 4LO. The green 4WD light and Amber 4LO lights blink as soon as I start the truck up and continue to blink no matter what.

The selector dial in my truck is set to 2H.

When installing the ADD I’ve made sure the arm fits inside the channel on the gray sleeve to lock or unlock the diff. I suspect I’m doing something wrong at that point and the sleeve is not in the correct spot. I’ve tried all the way to the left and all the way to the right with no change. I’ve even gone so far as to install the ADD without the black plastic cover so that I can verify the worm gears rotate and the arm moves the sleeve back and forth if I spin the front drive shaft.

At this point I’m wondering if A. I’m just installing the arm on the ADD wrong and need someone to ID the correct position for me.

Or.

B. There’s a issue with the electrical plug that connects to the ADD and the actuator isn’t getting power from the vehicle. I’m not a mechanic and don’t know how to read the electrical diagrams that have been posted here. Can someone identify which terminal is the positive and ground on the black plastic case of the ADD so I can apply power to that and verify if the arm moves once it’s assembled? I also want to check the wiring coming off the vehicle.

I’ve disconnected the battery and reconnected it in the hopes that that makes a difference. No luck.

Bear with me, I shoot guns not work on trucks or wiring so I’m trying to work through this as best I can. Any help would be appreciated.

 

The two heavier gauge wires are the motor power. I believe they are red and black.

 

Well after I replaced the front ADD with no results I took it back to the dealership.

After 2.5 hrs they found the issue! A Gawd Daym pinched wire on the wiring harness.

The service dept was very apologetic for not finding the issue the first time and only charged me 1 hour labor and no charge for the wire repair. Good on them I thought.

All is good now and hopefully it stays that way.

 

by chance did you see this pinched wire with your own eyes?? before and or after the repair??

 

No i didnt

I picked it up after hours. Otherwise my plan was for the mechanic to show me. I havent had a chance to look it over yet