2001 Chrysler PT Cruiser Transmission

Code 700 just means there's a diagnostic fault code stored in the Transmission Computer. Most likely that code is going to related to the input speed sensor or the output speed sensor. Those are what the computer uses to calculate vehicle speed and shift points. Most code readers used by auto parts stores don't access any computer other than the Engine Computer. You'll need to visit a mechanic with a scanner. In this case a trip to a transmission specialty shop might be in order.

For the leak detection circuit, there's an entire book covering diagnosing each fault code. Be aware fault codes never say to replace parts or that they're defective. A part referenced in a code is only defective about half of the time. First the electrical wiring and connectors must be inspected, then electrical tests are performed to eliminate everything else before the part is suspect.