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Two relays + switch detailed 'window winder' schematic needed

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BRSpoilerA.jpg Note: Okay, the window winder schematic is for my Crossfire electric spoiler. The Chrysler Crossfire was built in Germany and all of the running gear, brakes, and interior switches are 'from' the 2003 Mercedes SLK320.

To repeat from original thread, I own (but will be selling soon) a Crossfire Ltd. (XF) which has the electronic spoiler. I've bought a top of the line XF which has a supercharger + larger brakes; etc; but has a but-ugly bolt on spoiler; and yes, the eBay spoiler I've bought will bolt right in in its place; there is NO spoiler info in the BCM; meaning I'm on my own electrifying the spoiler.

I've given up on having a 'unit' that automatically opens the spoiler at 63 mph, then closes on its own. I turned to trying a 535T Window Automation System with a single SPDT relay (schematic was in the manual). At rest it would turn about an 1/8th turn; stop; hold for 6-8 seconds; another 1/8th turn; etc.; no movement reversing/closing. So that's out.

When i hook up the wires directly from a new 12V battery it goes up quickly (5 or so seconds); then reversing the wires it quickly closes.

I'll add that though there are limit switches built into the spoiler, I don't want to complicate the 'process' but instead use thermal switches like on most window winders. You can ask for a wiring diagram but it's easier to just tell you: There are two wires to the motor with the + at rest. [The separate wiring loom for the limit switches has three wires going in with the common black wiring ground wires splitting off for each of the limit switches. I'll add that though the wires are in DIN, the limit switches appear to have 20 gauge].

Also keep in mind that the wiring from the switch to the spoiler will be roughly 13'. I plan on splicing 16 gauge wire to the existing 16 gauge 3' wiring loom with connector for the motor. I'll use the + from the nearby cigarette lighter and wing it for the ground.

So please add the thermal switches and any diodes, or? I'm assuming it will use a Spal type switch and SPDT relays. I'll need to know the specific number/letter for every wiring connection along with what specific type of diode if used along with the type and brand of the thermal switches. IF a two wire (20 gauge) can be made to work, that would be perfect, but fine with whatever (not too large nor miniature including depth) of switch is best.

I'm used to using vintage type of wiring loom schematics, not the latter type.

I'll be happy to pay anyone providing they are 100% sure the outcome works .

Have I forgotten anything?


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Hi, these endeavors you have procured and vacated sound feasible and simple enough , for example your spoilers 2 wires can hook up in a H-bridge configuration using a "Dual Post, on-off-on switch"(as example in your very first thread), to automate, switch is replaced with relay..., .... as for the 1/8sec problem it would be interesting to see the schematic you used, im guessing a 555 circuit? after relay is working we can work on what triggers each relay.

Im not sure what thermal switches are for, unless safety cut-offs from winter freezing, in which case you would not want to replace the limit switch with it, but instead include with it

EDIT: just found other post, the window wiring is similar... however I recommend getting separate (2 relays) per window, it is best to correct any wiring mistakes now... if you are out of room, may i suggest extending wires to a place where you can fit the whole relay module, ie 4 windows + spoiler = 10 relays

also i assume you want the original manual switches intact...?
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Dr_Doggy, you do realize that this 'project' has nothing to do with windows - only the rear spoiler as shown. The thermal switches (unless I have the incorrect name) are merely inline 'units' which temporarily shut off the current if the motor is heating up. Even the vintage Alfa Romeos I restore have one in-line for the wiper motor. Regarding the 1/8 turn situation, there is no information available (that I know of) for how the electronic 535T Automation Window Automation System works, merely what color of wire goes where.

Regarding the switch: The spoiler switch on the SRT6's console is a solid dummy, but I do have an original working momentary spoiler switch which I'd like to use if possible. It has only a single wire for up and single wire for down. (Normally the spoiler at speed raises and lowers on its own). Even though I use relays on some of the cars I restore, I'm solely reliant on (to repeat) what wire goes where. My hope by using separate relays for up and down there would be no necessity of a center wire (unless for a light).

Minor, but I failed to include information on the small white arrow on the lower photo - it is the two wire down limit switch (the up is on the other side).


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so 3 wires? .... do i see 7 in the photo? ... also do you get a ohm reading from the switches when spoiler is 50% up (ie are they NO or NC)? and what is power rating of spoiler?

adding temp switch is easy then, just put it in series with the ground wire.... or better is to put it in series on the main power rail before all the switches, to select the right one we need to decide what temperature triggers it and how much current it needs to handle

A controller is simple single relay if limit switches are involved,

the only part i see is a bit challenging is how do you determine your speed? does Tachometer on car have output wire(s), what kind of data is on it? With that info solutions would be simple...
which is what a gut feeling tells me is wrong with your 535T Automation Window Automation System(assuming it is ok to use with spoiler), i have a feeling it is not reading the speed right... i wonder if there is a setting somewhere for different makes/models,?


BR2RelaySwtchB.jpg BR2RelaySwtch.jpg Where did I go wrong? Okay, there are no guarantees on most anything on the web, but the schematic looked professional. I hate it when I get schematics which don't show how the wires are hooked up to the switch and which type it is. The problem is that the second I connected the battery cables, it ran. And since these motors have a ton of torque and the outer wall of the motor is not mounted solid - meaning so it can't turn - but these do so the entire motor twist around screwing up the tiny connectors. The lower photo is an extra motor I bought so I won't install it until I know I can control it with a switch. I'm 99% sure I have the wiring correct except for the switch or type of switch.

Does the schematic appear to be viable or is it an incorrect switch?


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Pull all four of the wires off the switch. Apply power. Nothing should happen.

As it's wired the (#86 terminal to one relay or the other) to +12 should cause forward or reverse motion. It's OK to connect these wires manually.

If you want a safer test, disconnect one side of the motor and do the test above, one or the other relays will click.

You can also connect a DVM to the motor wires. Leaving one connected is OK. As you do the forward/reverse test,the polarity should be zero, +12 and -12 depending on which #86 terminal is connected to +12.

You need an SPDT momentary switch where the center terminal goes to +12 and the "ends" go to each terminal #86 respectively.

Your switch: IDK (I don't know).

NOTE: There is a preferred polarity of voltage to the coil and the Internet has it all messed up. If it's wrong, we'll fix it. It is highly suggested that diodes be put across the coils.. If you don't do it, other electronics in the car can fry. See: https://www.google.com/url?sa=t&rct...kZmwI6jL128VPziUw&sig2=UOyGbMI3_X8nLKUN5pGT1g

Ignoring that, you get to pick and some pick wrong, when the relays are at rest, the motor is shorted through both relays. This causes the motor to stop instantly. You can do it the other way too: Both ends of the motors sit at 12V when at rest. I don't like that one.

You also get to pick like FORD and CHEVY: do you connect to _ to turn on the dome light or do you ground the dome light. In this case pick the safer one. You get to pick again. It's easy to electrically switch something to ground. Stray +12 wires all over the place makes shorts hard to find. If ground did the switching, then you might just have a light on all of the time instead of a blown fuse.

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I want to discuss using the limit switches, not using the OEM dash switch and safety, or the lack thereof and possible options that still fall in the easy category. The spoiler deploying automatically is a safety issue.


But first, I need to tell a story. I was building the controls for a 3 track+loading dock with 9 boxcars each. So, at the push of a button, the loading dock empties on one track at a time. The loading dock is an oval chain with pegs pushing the cargo. In the end it was a 20 minute process. They guy is a basic farmer that builds model railroading for people that have more money than brains. His words-- Not mine.

He thought I could build the electronics sight unseen and we're talking 30+ years ago. Well, I got one motor, but not all 4 of them. One happened to be a brute and it had to be handled differently. Naturally, the small motor design doesn't work. Not enough current in the H-bridge driver.

His idea was to propel the gantry by electrically activating the required # or rails. In theory, it seemed OK. In reality, I needed to use the rails as a sensors.

The initial build was a breadboard that was proof of concept more than anything else.
In the end I needed one extra port, but we quit there. A manual switch was used.
The crane length was a mechanical mess. Multiple coiled telephone cords were used for both gantries. It was written in assembly language and hand assembled with no compiler, so it was tough to make all of the axis move at the same time. We learned that the dock had to stop in one position to load and another to unload.

The later version did incorporate motor shutdown if something jammed. It could be manually operated which added complexity, but made debugging a snap. It was made modular: x/crane drive, y/dock drive, x/y sense, magnet/crane drive, computer, power supply.

He changed the dock switches from something I liked, to something else which also required a logic change. The dock stopped on it''s own once started.

I researched a better cord or the gantry.

The crane had up/down electrically set limits as I suggested, BUT no servo operation. It would have been good to turn off the crane when the x gantry was moving. Yep, he did something else without consulting me. The y gantry used sliding contacts, so the crane could move down more or up more, but it worked. The computer was a single board computer programmed in BASIC which had to have one IC changed so it would reset properly, otherwise the gantries would slam into the stop, so it was nice to have simple motor protection.

An additional switch set the load. unload mode automatically. In the end, you had power and "go" buttons.

So, one proto and two nice ones. He did get a featured article in a model railroading magazine.

I often wonder how I would do the same thing today.

It's the same here. The specs are not complete. It's the motorized curtain vs the front end loader and you don't know what's important.


The point here is proper specifications makes things go really well. When I wrote computer code there was a lot of "You can do that". It was nice to explore an interface without any underlying code to get the information you need when one of the parties is clueless.

So, let's outline it, but Biba has to do this
* I have this and I want to put it in that. It mechanically .

* The way it works in the car it was designed for is described here (A document exists)
it's a high torgue motor that that draws x Amps unloaded and Y Amps when it;s deploying at 63 mph and Z amps when it's retracting. (This puts a box on it)

* It takes about c seconds to deploy and about the same to retract.

* the motor terminals are marked (whatever) and when a is more positive than b, the spoiler deploys. They are 0.250 faston terminals. OEM wire colors would be nice here.

* the spoiler has two limit switches that close at the limit. They are low current contacts (known value somewhere <<100mA or do) So, it's basically a common, retracted and deployed. The contacts are designed for logic levels.

* the wire colors are (x,y,z) and their functions are.

* the switch used is wonky and would probably have to be reverse engineered somewhat.
[It looks like they create voltage levels with the aid of an external resistor based on retract, stop and deploy]

*The switch I believe also has a LED with some interconnections. There also may be dimmable illumination to this switch. I know very little about this switch except I have an extra one. Here are some schematic snippets from the service manuals.

The lamp usually functions in this way. Is it bi-color. 1 wire or 3 wire, common adode, commode cathode etc, When does it blink?

* Auto-retractions looks like it requires a part that starts at $300.00 and I don;t want to do this at this time. (My response is that you have to access a CAN signal in the engine bay)

* The functionality I'm looking for is this as a minimum and this as a maximun with prices negotiable but within these general limits.

You need to fill in the blanks..

My response sits somewhere about here:

My comments since I had a much longer time to mull over it. The limit switches are a safety issue. A fuse could blow if you suddenly reverse the direction. The OEM switch is anything but easy to interface. It wants to interface to a microcontroller.

An SPST momentary center off switch ought to work

I take no responsibility on any safety issues that would arise.

Some items need to be discussed. I think I can easily do the limits breadboarded. Within that design come some possibilities for LED use.

1. EASY(independent of limits): RED/GREEN bi-color LED. Direction and moving would be conveyed by color. e.g. Moving UP would be RED; Moving down =Green. Stopped = OFF

2, Some variations on Single LED Bi-color to indicate fully up or down. Dual led to indicate fully up or fully down. Color indicates which.

3. A light to indicate - not at a limit.

I think you need to know if the spoiler is fully deployed or fully retracted. Moving is a secondary issue. Blinking is more of a processor function that something isn't right.


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you look viable at first glance of schematic, however you do not need ground wire in power switch, unless it lights up, more of your problem is most likely the wiring, and/or maybe there is difference in the relay you used compared to schematic:

do you know how to read ohms and conductivity, ohms is the horse shoe symbol on a voltmeter?
0.5) disconnect power!
1)to test your switch, push and hold the button down.... then measure ohms on the contacts , when you find the right contacts, ohms should be near 0 when button is down, and very high when button is up....
2) do for other wire/switch position too
3) 1 out of the 3 contacts that worked in above test will be the same for both, that is the wire you hook up to 12volt from battery

for the relay it could help to show part number of the item , sometimes they have a schematic right on them....
the relay is a simple/fascinating device just like a switch:

in this example, it may or may not be same pins as your relay, but they are all basically the same:

in the top part you can see the basic switch on pins 30, 87, 87a and it is tested just like the switch above....

you could have 1 of 2 problems .... something wired wrong or something shot... either way needs ohm testing with no power hooked up .... or voltage testing if power is hooked up

.... actually your switch does look wired wrong ... in a typical switch main power goes in the middle, and each direction is on the sides, but jus a guess, ohm test mentioned earlier is best... another testing option is to cut out the switch and apply power directly to one of the wires going from switch to relay


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ya... look at the black wire, that is his power bus.... that looks to be a strange config...
when he pushes up power MAY go to red and also powers relays,
when button is down no power going to either relay even if it is right pin feeding power and power makes it to green through switch, there is no power on relay even if activated
.... All the black wires should be on the same node (connected together) and black should not be touching red green directly.


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I'm confident that I could build/breadboard a circuit that uses the low current limit switches. It would be used in addition, to the relay set-up that your trying to build.

What I think can minimalistically work is a small switch such as http://www.digikey.com/product-detail/en/c-k/T105SHZQE/CKN1088-ND (3A rating) and a Bi-color LED such as: http://www.digikey.com/product-detail/en/everlight-electronics-co-ltd/MV5437/1080-1109-ND/ shown below.

Images courtesy of Digikey. There is a bushing that can be used to mount the LED.

The functionality would be as follows:

1) Low current limit switch operation: Around 10 mA
2) Transient protection/reverse polarity protection - nothing heroic
3) It should be powered with 12 V that need to go away if the motor fuse blew.
4) No undervoltage lockout
5) Flipping the switch on and off rapidly could cause the fuse to blow.
6) Pick a color for up - Green? (it's the safe position)
7) Pick a color for down - RED (It's an unsafe position)
8) So it would glow green when fully extended, and red when fully up. OFF when indetermanent.
9) No brightness control for the LED, although it can be fixed. Selectable with a component change. Probably not variable.
10) Breadboarded --> not a commercial PCB.
11) Screw terminals probably
12) No case.
13) It was mentioned somewhere that the spoiler could interfere with trunk and top operation. No provisions to stop that from happening.
14) I'd have the SMT parts soldered to a DIP header to breadboard the PCB.
15) I don't have a BOM (Bill of Materials) or time estimate yet).

It would be ideal to use some sort of connector and/or interface to the OEM connectors. e.g. the limit switches.
You would have to run a 5-wire (educated guess at this point) (shielded preferred) cable to the console switch area. Connectors are probably a sore spot,because the tool to crimp the wires is about $70.00. Delphi makes some nice automotive connectors. The LED can have a connector that connects direct. We would need to find a convienient place place to connectorize the dash area. You also need fused 12 V power for the spoiler. That same power has to power the circuit for safety reasons.

Possible options:
a) LEDs on the PCB that mimic the limit switches.
b) LED or LEDs on thr PCB that indicate applied polarity to motor.
c) A second switch/LED combo that can be plugged into the trunk connector.

Mating connectors would be nice. Especially the motor and limit switches.

Thermal PTC thermisters that get mounted to the motor have to be sized properly.
The fuse should be selected to blow if the motor hits a brick wall. To get a better selection, you may have to resort to another holder. Both of these have to protect against a failed limit or something gross getting in the way.

Future total unknowns:
a) How the switch is wired. We know there is a resistor inside and two terminals that select up down and one of these terminals probably goes to +5 via resistor.
b) The malfunction LED PROBABLY has two terminals? What is the voltage and/or current?
c) How is illumination of the switch handled?

The malfunction LED probably is probably wired directly to the BCM. I can't match the ICON to the BCM icon in the SM. The voltage/current is unknown.

So, the switch could have from 5 to 7 terminals on it? It needs to be reverse engineered to even think about using it. One issue that MAY need to be solved is the prevention of movement while the control circuits are powering up.

With significantly more effort, the OEM switch can likely be used, but now, I'll bet we don;t have access to colors.
So, you have options of "moving", "at any limit" and possibly "between positions". I think "between positions" would be the right indicator, but harder to do.

I have no idea how the console illumination (dash lights) is done. Some radios use a "DIM" signal that just lowers the illumination brightness which is usually fed through say the parking lights being on.

Using the torque specs, it may draw less than 1 Amp. It would be useful to know what it draws no load, raising and lowering and even raising and lowering at high speed as well as stall. The DC resistance would be difficult for you to measure, but that would give me a ball park figure.

Knowing the current requirements for the motor can likely make the unit smaller.

Fully automatic operation
I'm not in a position to tackle this at all. With a microcontroller and a $300.00 USD interface it would seem you can get access to speed on the CAN bus in the engine compartment.

There appears to be 3 speed setpoints. deploy, retract and alarm (chime when not deployed when > some mph) "Chime" might add one or two more wires tot he front.

It would be somewhat useful to video the deployment/retraction and see if there is a program (VLC) that can view the file in slow motion, to figure out what the stepped actuation is all about. How many stages and how long they are.


At this point in time, I might be able to do a PCB layout with an online type of program. It may change in the future. I definately have a large learning curve. I did it manually (no computer) some 40 years ago and with a DOS based program probably 10-15 years ago.

Does any one else want this thing? At what level of functionality? At what price points? I would want no liability. Besides that, I can't control how something would get installed.

When you rely on a fuse for protection, as soon as it's replaced with a higher value all protection goes out the window. That fuse is the only insurance against a failed limit switch. Hopefully a PTC attached to the motor can be added as well.


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Professionally Done Wiring

Look at the bottom of real page 15 and the top of real page 16. https://www.parts-express.com/pedoc...ring-diagrams-installation-guide.pdf?#page=15

Those are your choices. Pick one. The only difference is one uses a contact to ground and the other uses a contact to +12 to activate. if you activate both relays at the same time, nothing happens. e.g. the motor doesn't run

This dual socket https://www.parts-express.com/12-vd...socket-for-door-lock-unlock-circuits--330-078 pretty much does the wiring for you.


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So, I also learned recently that you get a chime when the spoiler is fully lowered. So if the OEM switch is used we may be bale to do the possibility of: not at either limit for the LED and a chime at the lower limit. So instead of the LED indicating a malfunction, it indicates it's not fully extended which is, in essence, a malfunction.

Look for a suitable chime module.

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