Another 4x4 Flashing Light but not what it seems.

I've had a flashing 4x4 light for almost a year now and kind of gave up on it but recently I've been diving back into getting this issue finally resolved. After some research on here I have found that the faulty points on the actuator could be an issue. So After pulling out the actuator from my truck this morning, I was able to solder the points, test with a portable jumper kit, and actuator is responding properly. I've put this back into my truck and still flashing lights when going to engage 4x4.

Edit: I went out again and re-checked the ECU as well as the switch. The switch seems to be working, as when I switch it from 4-hi to 4-lo it still blinks but at a different rate. The vacuum lines do not look damaged. Going to open up the T-case actuator tomorrow to see the condition of it then I guess check harness/ wire outputs from there.

Also,a few years back I had found out a little rodent had chewed a wire in my engine compartment, which although it did not effect anything in the vehicle, I properly repaired it without spending the boatloads on a whole wiring harness that runs throughout pretty much the whole front end. Could there be a further issue within this? At the time the 4x4 was working properly, but is there a way I can check the connections to properly diagnose this issue without completely pulling things out from under the hood? In reality I just want to be ready for snow this season in VA so have a couple months to get this fixed if possible

Thanks!

 

When you switch from 2H to 4H, what *actually* happens? Do both of the actuators actually RUN?

The ADD actuator has a worm gear and hooks up to the collar via a spring. There are two switches. One measures the position of the "drive" side of the spring, and the other measures the position of the collar on the shaft. If the splines on the shaft don't align with the collar, only the drive side switch will indicate "engaged". It can be necessary to turn the steering wheel, or drive a bit, in order for the collar switch to engage, indicating that the collar is actually in place. If the collar doesn't engage, or the switch doesn't work, the light will blink. If the drive side switch doesn't indicate engaged within the timeout period, the light will blink.

You will need to use the wiring diagram to check the state of all of these switches when you switch it to 4H. Possible problems I can suggest for ADD: Drive motor not running, drive side switch not reading correctly, collar stuck, collar side switch not reading correctly.