4WD Switch Repair

[41canine]

Another 4WD Switch Fix

I had the way too common 4WD selector switch problem; not going into different modes, setting off the "Service 4WD" message, and occasionaly changing to 4WD by itself. I was prepared to check for bad solder joints, as suggested, or to replace the switch. When I removed it, I easily took it apart and it reminded me of a 'gummed up' TV remote contol. I took a cue tip, and using denatured alcohol, cleaned the circuit board and, more importantly, I removed the rubber part that activates the switch mode and cleaned the brass buttons on the back and reinstalled it. It works perfectly. Changes into any mode at the push of the button, goes into the neutral mode when set, (which it would seldom do) and NO MORE SERVICE 4WD message. The message would ALWAYS come on within 30-35 miles. Over 100 miles now and no message and all modes still working. Temporary or not, I don't know, but it's on a '99 Silverado and it's had plenty of time to get "dirty". Just a suggestion.
Bob