No Speed Control When Set Button Is Pressed & Released
WARNING: This page is about a different car, the 1996 Chrysler Sebring. However, it is still accessible from the selected car via links, so may be relevant.
Check for: blown fuse, no vacuum at servo and/or defective servo, disconnected speed control cable, brakelight switch out of adjustment, faulty electrical circuit, faulty Manual Valve Lever Position Switch (MVLPS) input to PCM and/or faulty PCM.