Hello, was looking for some help with this truck. 4wd light flickers, when truck is not actually in 4wd. Once you engage the 4wd in either low or high, the light will come on and stay on. The 4wd works fine, but having issues with figuring out why light flickers in 2wd. I have already replaced the sensor on top of the transfer case, but that did not solve the problem. I am not sure if the vacuum lines are working correctly or if it is something else.