wulffpac

Greetings Forum,
I have a 1997 Grand Cherokee limited with a V8 four wheel drive with a NP249 transfer case. I keep getting a "service four wheel drive switch" notice on the information center. I have re soldered the little post as described on this forum and it fixed a lot of other issues but not this notice. My switch has a four pin plug. Is there a way of testing the switch prior to having to purchase a new one. I did a continuity test and the I have continuity between post A & C with out pressing in switch. there is continuity between post A & B when switch is pressed in. Also have continuity between C & B when switch is pressed in. Post D seems to be dead with no continuity between any of the other post even when switch is pressed. So, do I have a bad switch or is it good and need to look else where for the problem. Thank you very much for any help.