Speedo cable and 2 wire connection

[foss40z]

I have a question. I have a 88 bronco 2 that use to have a dummy transfer case (2wd model) .. i recently picked up a 94 A4LD tranny without a dummy transfer case from a ranger. i know 1 is a speedo cable, what is the other 2 wire connection used for? Also i am having issues with the new tranny going into overdrive. would not having the speedo cable and 2 wire connector hooked up to the transfer case cause the new tranny not to go into overdrive?

Thanks

 

[4x4junkie]

Very possible...

That is the vehicle speed sensor (and would prevent the cruise control from working as well)