Vacuum Line Switch Replacement - 4WD Light
After replacing the front axle vac harness (which had vac lines cracked in several places), the 4WD light on the dash glowed all the time. I narrowed the problem to the vacuum switch on the T-case (Jeep part #53001101-- $21US, Quadratec charges $14). It is a bit of a bear to get to and remove, but it can be done with a 10" (250mm) adjustable wrench and by shifting the T-case into 4L. There is also a seal (an "O" ring really) on the vac switch that should be replaced while you are at it. Jeep wants $4 bucks for the thing, Quadratec charges $1 and Home Depot has them for 35¢...go figure. Once the new vac switch was on the T-case and the harness was reconnected, the shift motor worked as it should and the 4WD light came on when in 4H or 4L only.
I appreciate the feedback and advice provided by Chris Waterman.