Currently having some issues. 1997, the seats are not moving, the odometer does not show, and the windows do not work. Last time I drove long distance was about two hours and had the "reduced engine power" warning. What is wrong? What needs to be replaced? How much will it all cost?

 

Are you able to see any trouble codes in the DIC in the cluster ?
If not you may have a corrupted/shorted serial line and you can try to remove the star connector to the seat/door modules
in order o locate if these problems are causing any of these issues .

These connectors are located on the left side of the body control module in the passenger footwell .
Remove ONLY the connector with four wires.

If you have a multimeter I upload some schematics if the above test not give any respons

 

Also a Reduced Engine Power mode is normally set if you have error within the TAC system (TAC module, Accelerator Pedal Position Sensor or Throttle Position Sensor ) .
But this will normally set one or more DTC's on your Digital Information Center .

Also if you have ignition switch with defective contactsets due to long time wear you can have similar symptoms .

If you measure the voltage between battery positive terminal and Minifuse 18 ( point A or B) shown on the schematic below you shall not measure more then 0.1-0.2 volt
If the contactset of the ignition switch is burned due to "high current wear " over 30 years these contact sets can cause several volts drop over the contact sets .
This will result in too low voltage to the electronics supplied by the voltage from the igntionswitch and strange things start to happen .
If you measure this voltage with engine running and some current load to system(Lights/AC on) , this will show the voltag drop over the ignition switch better ( if the ignitionswitch is your problem).
Voltage drop equals to resistance x current (ohm's law)

Do these checks and report back .

If the problem is a faulty ignitionswitch these will cost only approx .USD 70 in parts