4WD Issues

Back story: Hi, I have a 2006 sequoia limited. I was told by the guy I bought it from that the 4x4 does not work. I have been trying to fix the 4x4 so I can take it overlanding.

Signs and Symptoms:

* The 4Hi light will just randomly start flashing while I drive.
* It gets stuck in 4Hi.
* Sometimes it will shift to 4Hi and 4Lo just fine, but the moment you try and go back to 2WD the 4Hi light just flashes.
* Sometimes if you are real quite you can press the 4hi button and hear the actuator, but other time you can press it and hear nothing. It is almost like it is only getting power sometimes and not others.

What I've done:

I had an abs code pop up for a RR wheel speed sensor. I seen that, that could cause an issues with the 4WD, So I replace the sensor. No longer getting a code for that. In fact I am not getting any codes.

I am not sure where to go with this because I have also talked to a dealership about this and they have also been stumped. Any one ever had this issue or know where to go from here?

 

Start here: https://www.tundras.com/threads/so-you-wanna-buy-just-bought-a-1st-gen-tundra-eh.115928/

Yes, that's for Tundras. But if you scroll down, you'll find this:

• If you're reading this because your 4WD isn't working and you need help, check THIS REPLY for some helpful troubleshooting steps to take.

That is literally everything you'll find poking around this forum to help you with 4WD diagnostics in the 1st gen (regardless if Tundra or Sequoia)