I just purchased a 97 2500 4x4 cummins Automatic at an auction. I have an issue. The tach, speedo, cruise, OD, are not working. I have been doing some research and just wanted to get as much info as I could before I start buying parts. I have taken off the crank position sensor and cleaned it up, would like to know if there is a way to test it before i re install it.