relay: (We have to wait until you get your multi-meter and take some really baby steps here)
From the other post;
https://www.electro-tech-online.com/attachments/relay-bosch-0-332-209-150-jpg.102749
Understand the relay
I'm assuming the relay diagram is on the relay. It might not be. Watch out for views: Is it viewed from the bottom or the top?
Using polarity conventions:
Baby step #1, assuming one relay and a (motor or a lamp).
Identify the coil: Measure it with your ohmmeter. It should read a few hundred ohms between terminals (88) and (85)
Identify the common terminal (30) and the NC terminal (87a). You should read close to zero ohms between these two terminals. Leave the ohmmeter connected.
Connect the battery between 86 (+12 by convention) an 85 (Ground by convention)
The relay should click. Feel it. Listen to it. The ohmmeter should read open.
Move the probe from terminal onto terminal 87a to 87. That should now read a short.
Remove the power from the coil (one side) and those terminals should open.
If the relay doesn't work - STOP.
Test the other relay in the same manor.
Test your switch
With a typical SPDT momentary switch (layed out as [1 2 3], the center terminal (2) in this case is the common terminal. If it is a bat handle toggle switch, follow the end of the bat to the back of the switch, so if the bat is on the (3) side, pins 1 * 2 are connected. Check this with your ohmmeter. When, you flip the switch, 1 & 2 will be connected.
Hopefully this checks out too.
Let's make this sort of system switch the positive voltage.
Don't connect to +12 and ground to the power source just yet, Just label them as such.
So, let's connect +12 to the common terminal of the switch and to terminal 86 of both relays. If you made a connector that daisy chains use that connector.
So, you will have the center terminal of the switch, the +12 supply and pin 86 of one or both relays all connected to +12. Connect pin 85 of both relays to ground.
Before we connect power, lets verify stuff is connected properly. With nothing connected to power, Put the ohmmeter where V+ and ground would go.
You switch should indicate a few hundred ohms when in either extreme and OL in the center.
Remove the ohmmeter and Connect power.
Flipping your switch should make one relay click, both be off in the center and the other relay should click.
When one relay is on, the other should be off. Terminal 87a will have continuity to terminal 30 of one relay and terminals 87b and 30 will have continuity of the other relay and vice versa, when your in other than the center off position. When the switch is off, 87a and 30 will be connected together.
I'll choose this turn.
OK, turn off the power and now connect pin 87 of BOTH relays to ground.
Put your ohmmeter between the two terminal 30's. It should read nearly zero.
Apply power with the ohmmeter still where it is. Momentary one way, OL (Overload) and the other way OL and the center , shorted.
Remove power and put the DVM into volts mode to potentially read +12 V.
Connect both terminals 87 on each relay to +12 Volts. Apply power.
In the off position, the voltmeter should read zero. In one direction aprox 12 V and with the switch in the opposite direction -12 V.
Your ready to connect the motor to pin 30 and 30, the common contacts.
The motor should move in one direction and then the other and stop immediately when in the center. For the system to work, both relays have to work.
The wires going to the coil can be lighter than the wires going to the motor. The wire from 87a to 87a should be short and then it can be returned to ground.
In the final game, a single (1N4001 to 1N4004) diode should be placed across the coil terminals of 85 and 86. The band on the diode would go to the + voltage. These could be easily soldered to the relay terminals.
So, instead of hooking things up and see if the magic smoke comes out, hook it up piecewise and troubleshoot along the way. You can substitute a lamp for the motor in all but the final test, but it won't show any difference for the change in direction.
So, very simply, the relay holds both ends of the motor at ground when unenergized. The CW or CCW relay just connects one of the grounded wires to +12 making the motor rotate in some direction. Stopping the motor, means the motor acts as a generator into a short and it stops quick. Trying to make it go forward and reverse at the same time is the same as braking.
The limit switches in the OEM spoiler have the wrong sense. Closed at a limit, rather than open at limit.
In a design of this type, the "close signal" would be "removed" when at the "closed limit" and vice versa.
The remaining reminder is that not all automotive relays have the same pin out. If for some reason, you accidentally put the relay coil in series with the motor, the relay would be toast.