How can I fix a variable speed scroll saw that will not run at a constant speed? The motor speed runs fast/slow, not at a constant speed, no matter what the control is set to.

Try a fuel filter

You have either constants or variables. Constants are things that does not change. Time is a constant - you can't move forward or backward in time.
Variables are parameters that change. Some variables are fixed, others can be controlled.
A controlled variable is a variable that can be changed at will or according to circumstance.
For example, if you have a radio with a fixed coil / tuning capacitor which can receive only one station, the variable (radio stations) cannot be controlled, it is fixed, therefore a fixed variable. A normal radio can be tuned to different stations, therefore a controlled variable.
The engine on a car has a controlled variable speed. A normal light bulb is controlled by a fixed voltage, until you build in a dimmer switch, which now makes the voltage variable, and controlled.

This is (obviously) a two-speed motor. The low speed winding is burned out. Replace the motor.

may be motor on way out ,,,,, the resistor for the system usually allows full blower power when set to top speed,,,,

I would change the fuel filter before anything else, however, a fuel filter would cause it to cut off no matter how fast you are driving.

Slow is the same speed as 'mist'. Mist is when you twist the control arm backwards to induce a single swipe. If you hold it, you will run the wipers in low speed. Fast is faster than that. Probably by 30% or more.

Turn the wipers on high speed. Wiggle the connector at the wiper motor. If the wipers run sporadically as you wiggle the connector, you either have a bad connector or a bad circuit board on the wiper motor.

Alarm control unit has a chip in that controls the delay wipers, this chip cost about 2 dollars, but it has to be sodered in. the whole box cost about 200 dollars. It is located behind the glove box on above the right kick plate ive been told. chip can be bought from mouser.

your problem is your blower motor resistor. change that and it will fix the problem promise!!!!

Ok, here are the wiring colors and functions/destinations. C0030 is the motor connector for the front windscreen.
C0030-1 - Black, runs to a Earth
C0030-2 - White/Green - Fed from the front wiper relay, via the IDM
C0030-3 - Blue/Green - Flick Wipe/Fast Wipe
C0030-4 - Green/SlateGrey - Power from Aux Relay
C0030-5 - Red/Green - Looks to be a speed control connection.

It's hard to tell to be honest, you'd really need to sit down with RAVE and the electrical circuit diagram and the operation description to make head or tail of it.

If you have removed the blower motor, Connect it to a 12 volt power supply(your battery)with some jumper wires.It should turn fast, be careful when you connect it, have a good grip on it, it will jump just a little. If it dont run fast its junk. The other 2 things
1)The fan switch
2) The resistor that slows the fan at low speeds.