The Code P0700 is Transmission Control System Malfunction or the Transmission Computer.
The only thing so far I have been able to find on Code P1789 is OD/2-4 HYDRAULIC PRESSURE SWITCH CIRCUIT. Which could be just the Selenoid Pack.
But let me do some more research and I will get back to you.
Friday, February 20th, 2009 AT 8:43 PM