4WD issues, please help!

Good evening everyone,

I have been having issues with my 2008 Toyota Tacoma V6 4.0 liter 4x4 (please see my previous post). Needless to say, I didn’t get any help from the dealership and they just wanted to start replacing parts to see if it worked.

I have replaced the front ADD actuator. The green 4WD light still blinks and will not go into 4HI. I have checked and cleaned the ground wires. All connection harnesses are very clean upon inspection. I removed the transfer case actuator, it passed bench test ok. It was a bit stiff, but has loosened up and runs fine when bench tested.

Now, the transfer case was easily going into 2HI, 4HI, and 4LO when I would manually turn the gear inside of the transfer case actuator. However, at one point when the 4WD light was blinking, I went to remove the TC actuator solenoid/motor and it spun under a lot of pressure when I took it off. Since then, I cannot get the TC to go into 2HI. I have removed the entire TC actuator and the front driveshaft is still locked in 4WD (could be locked in transfer case or possibly front differential).

looking for information about the transfer case shaft which the transfer case actuator connects to. Does anyone know which position corresponds with 2HI, 4HI, and 4low? I believe all the way forward is 2HI, but I’m not sure. And how difficult should it be to manually move it between these positions?

Thanks for all of your help!

 

I am surprised nobody with 4x4 have chimed in since these 4x4 setups in the Tacoma are so problem prone.

 

All the way IN for 2HI
All the Out for 4LO

 

If you have time, this has a lot of good information.
All a out the 4WD System on these trucks.

https://www.tacomaworld.com/threads/transfer-case-transfer-cases-in-first-and-2nd-gen-trucks.345652/

If you read far enough down the page.
“Flashing light 4WD” is listed as well.
Hope it helps.

 

Thanks guys! I found a video that demonstrated manually shifting the transfer case rod, and mine seems to require the same amount of force to move through the same positions. However, even in 2HI (Manually set in the transfer case) the front drive shaft is still stuck in a locked position, and is turning when driving. Any ideas of transfer case problems that could cause this?

I will check out the provided link to gather more info. Thanks again everyone, it is greatly appreciated.

 

Is the front diff locked in 4WD?
I think this could cause the drive shaft to spin as well.

 

Also when you pulled the front actuator, did you look to see what position it was in?
For reference read here
https://www.tacomaworld.com/threads...uator-or-t-case-actuator.358059/#post-9674854

 

I will jack all four tires tomorrow and see if it spins or not to determine where it is locked

 

yes, made sure it was unlocked position, all the way towards the passenger side of the truck.

 

Good morning everyone!

I jacked up the truck this AM, determined the front actuator was locked in 4WD (front tires didn’t turn when truck was in gear, but did turn when I Manually turned the front driveshaft). I took the transfer case actuator cover off and manually place it in 4HI. Got in the truck and placed it in 4HI at the dash switch. The green 4WD and 4LO Lights flashed rapidly And continuously, but the front wheels were spinning under engine power

so I have determined that everything is in the 4HI position now and is operating as normal. However the fault lights are still flashing. I’ve disconnected the battery. Next step is to test the position sensors in the TC. Any other advice? Also can someone give a quick guide on how to test the position sensors? Thanks!

 

Tested the TC position sensors. Both are working appropriately. Green 4WD light and 4LO light still flashing rapidly when ignition turned to on. Any further ideas?

 

I am assuming at some point when we were working on the TC actuator and manually manipulating it or changing the Dash switch, the TC actuator activated the front ADD actuator into the 4WD position. I am going to remove both actuators and manually place them in 2HI position, then put it all back together and see what happens. Position sensors are good, but no guarantee there isn’t a short in the wiring somewhere. Not sure how to test that

 

I pulled both position sensors, tested for continuity when in the open and closed positions. Both worked appropriately.

 

And thanks for video. Already replaced the front ADD. The forks were stuck in the old one, once we loosened them up it passed bench testing. But I had already bought the replacement part and decided to put it in instead of having a reoccurrence in the future

 

Quick update:

I applied power to the front ADD to move it to 2HI position. Confirmed by turning front driveshaft and individual front wheels to confirm. Transfer case is in 2HI position as well. Dashboard switch is in 2HI position. Still getting flashing 4WD and LO lights on dashboard.

All grounds are good. Position sensors are good. Contacts for wiring harnesses are good. Any further suggestions?

 

Great thread, thanks everyone. My new issue may or may not be related...??
My 2010 Tacoma goes into 4WD, high and low, just fine... also the rear locker engages. But, when I go back into 2WD after first unlocking the diff and going into H4, the 4x4, Low Range, and locked diff indicator lights blink rapidly. My truck is in 2WD at this point but the 4x4 Lo, locked diff light is blinking fast.
I go back into and out of 4WD and shut the truck off and on to finally get the blinking light off. This has happened now the last two times I put it in 4WD. What needs fixing??? I will continue to search for an answer. Thank you!

EDIT: I made a new thread for my problem: https://www.tacomaworld.com/threads/4wd-indicator-blinks-rapidly-when-returning-to-2wd.705201/