4x4 blinking even though I checked everything I can.

[vladen32]

Hi everyone,

The problem I am facing has so many threads but I have looked through a lot of them and none of them helped my case. I need some assistance with an issue I'm experiencing with my 2000 4Runner's 4x4 system being stuck in 4x4 and the indicator is blinking. (when I pull off the actuator cover on the transfer case and pull the shaft out and put the actuator back together it works. As soon as I click the button it gets stuck in the blinking mode and in 4x4). Despite extensive research on various forums and YouTube videos, I haven't been able to pinpoint the exact cause of the problem. Most resources focus on the "j" transfer case, whereas mine is the "I" version, which is fully electronic. I'm at a loss for further troubleshooting steps and would greatly appreciate any insights or suggestions the community might have.

Issue:
My 4x4 indicator light is blinking, and it seems like my vehicle is stuck in either all-wheel drive or 4x4 mode, since when I try to turn the wheels skip. It's important to note that I don't have a differential locker, so the skipping is not due to that. Given these observations, I suspect that it's stuck in center locker mode, as all-wheel drive technically should exhibit this behavior. (Feel free to correct me if I'm mistaken.)

Steps Taken:

1. Tested the two switches on the actuator for continuity, and they passed.
2. Checked for continuity on the buttons inside the car, both when engaging the center locked button and the 4x4 button on the transfer case knob.
3. Disassembled the actuator to inspect its interior, which was found to be clean.
4. Confirmed the motor's functionality using a 12v battery.
5. Removed only the actuator cover, spun the gear responsible for engaging the shaft in the transfer case, successfully disengaging from 4x4 with indicator lights turning off. However, the issue persists upon re-engagement.

Suspicions:
I know that 2000-2001 had a 4x4 module it could be that. Or possible the front actuator but I have no idea what the point of it is? and if I should check on that as no-one really mentions it. It is also super hard to get to, so that is the last thing I want to do, unless you guys think it's a high chance it's that. I don't want to be throwing parts at it as parts transfer case is $300-$400 so I might as well change the whole thing, but then it would be a waste to throw the whole thing away for a simple fix.

Also, I had a suspicion that it might be that the transfer case actuator motor doesn't have enough power to push it into 4x4. Could that be? How would I test this?

 

[phattyduck]

Since you mentioned blinking 4WD lights, I will assume you have a Limited trim...

The '99/'00 Limited still has a "J" shift pattern, but the 2H to 4Hlocked movement only actuates a switch that indicates to the 4WD computer to switch to that setting. There should be a "4WD" button on the side of the shift knob for 4H-unlocked (AWD mode). If your '00 does not have this setup, you may have the wrong transfer case in your truck. How much history do you have with it? The "I" shift pattern cases are either the '96-'98 Limiteds (non-multimode but electronic 2-4H shift) or the '01/'02 (all trims, multi-mode with dash button and shifter button).

It should be fairly easy to verify the front actuator is disengaged or engaged by checking what drivetrain element is free or locked. The ADD system (front diff actuator) disconnects the right/passenger side output of the front differential in 2WD and connects it in 4WD/AWD modes. If the right front wheel spins (lift the front) without moving the left CV or front prop shaft, it is disconnected. If it moves the prop shaft or other CV, it is connected. No need to get in there more than that right now.

Next, when reassembling the actuator and the transfer case, they have to be timed correctly with each other or you will get all kinds of shifting problems. That's likely what you are experiencing at this point. I don't have details for that...

-Charlie