Trouble shooting the 4 wheel drive on my S110P. Has push button on dash to the left of the steering wheel, no Hi/Lo lever between seats. When the 4x4 button is in the out position (4x4 engaged, right?) I do not get an indicator light on the instrument cluster indicating that 4x4 is on. I found what I believe to be the vacuum controller for the front dif under the passenger seat. When the button is pushed in and out, the vacuum controller doesn't click. Should it? I only assume it should because while pressing the button I heard a clicking coming from the rear of the truck and isolated it down to what I think is the vacuum controller for the rear dif. I am waiting for a copy of the service manual to be delivered but was trying to trouble shoot without it. Also, how do I go about testing the vacuum lines to see if they are bad? This may seem dumb to ask, but how do I test to see if the 4x4 is working or not, is there a way to test in the garage? Thank you for your help!
