4wd Wire harness

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That guy doesn’t know what he is talking about.
The switch wires don’t go to the actuator, they goes to the 4WD ECU.
The 4WD ECU controls the rest.

How determined are you to figure this out?
We have a comprehensive diagnosis thread on this, with very a high success rate of repair.
But you will need to check a few readings at the 4WD ECU.
You’ll need a voltage meter and means to probe the connection.
It’s all laid out for you in the link below.

https://www.tacomaworld.com/threads/4wd-system-operation-help-thread.742420/

 

I had a feeling there's a controlling brain(ECU) somewhere in between due to the fact that it turns on but not off unless it's powered down. Because if it's only hardwired, then why on but not off?

Thanks for the quick response!

 

I don't think there is a separate harness for the 4wd, I'm pretty sure the wires going to the Transfer Case are part of the Transmission harness. The ADD on the front axle has a short sub-harness under the engine but I believe everything else is part of the engine or transmission harnesses.
It may very well be a problem where the harness was repaired but typically repairing a harness is much more feasible than replacing it unless it's damaged so bad it can't be easily repaired.

If your comfortable using a meter and backprobes grab the form in the thread @TnShooter posted, check the voltages, and post your results.
Also 09 4wd wiring diagram posted below.

 

I’m pretty sure it isn’t a separate harness.
Replacing the harness would be a big job.

I would probably see where the issue is by doing the probs at the 4WD ECU.
Never trust the previous guys word, as that guy might not know what the problem is.
Until you made that thread, most guys just “guessed”.