The p1698 sets when the other modules on the van are not receiving bus communication messages from the transmission control module. If the module goes down the shifter boxes won't show correctly, and the trans will stay in second gear. You could have a wiring problem, or it could be the trans controller itself.
This is a faulty in the antitheft/security system. The security module and bcm(body control module) need to be read for stored fault codes to know where the problem is