The dreaded flashing 4x4 lights

So I’ve got both 4x4 lights flashing and no 4x4 engagement. I checked the limit switch voltages but I’m not sure where to go from here…

 

@Dm93 might have a clue.

 

Just looking at voltages it looks like an issue in the ADD Actuator.

Have you checked if the ADD is locked in?

 

I just went and looked, I see we were chasing an issue with your 4wd before. Is this still the same issue or something new?

https://www.tacomaworld.com/threads/no-4wd.798778/

 

Check to see if your front driveshaft is locked in. If so most likely gonna be the front actuator

 

Yes, unfortunately I’ve been here before chasing the same issue and never did figure it out. I finally took it to a shop and they threw in a new ADD actuator even though I had already done that. Pretty frustrating.

Front driveshaft is locked in.

I’ve chased the wiring from the ECM to the ADD and not seeing anything wrong there.

 

Have u ever removed t-case actuator? Timing gear may be off. Also check both hoses check for cracks pr tears.

 

Have you checked circuit integrity on ADD, DL1, and DL2?
They should all be 12v at the 4wd ECU with the ADD Actuator unplugged, and should be 0v when you ground them at the ADD Actuator.

 

Ever figure it out? I've been having this problem since July but every time I take it in the light goes off and it starts working and they don't do anything

 

According to your profile you have a 2022, which while the system operates in a similar manner it is different from the 2nd gen system and should be much easier to diagnose being it can set trouble codes and you can see live data on a scan tool making testing much easier for someone that knows what they are doing.
Intermittent problems can be really difficult to track down because the problem needs to be present to do any valid testing so many techs won't bother spending much time chasing a problem if it can't be duplicated quickly/easily.