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J

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Discussion Starter #1
I keep having the limit switches go bad on my rear active aero, as I know well that others do too. I plan to eliminate these switches utilizing an infrared sensor detector pair and some solid state electronics, instead of mechanical switches. I've even thought of selling these once I get it working, perhaps even installing these for folks with this trouble, maybe having your spoiler motor assembly shipped to me, fixed, and sent back. Anyone interested in this?
 
M

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That would be great!!! If that is why mine doesn't work?! Took the motor out and cleaned it up, hooked it up directly to my battery and it worked fine, just didn't when I put it back on the car??????
 
J

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Yes, you are right! It does have something to do with cold temperatures. Cold seems to make the limit switches fail.

Mr. VR-4, your limit switches are exactly why it doesn't work. I've replaced them on 3 occasions, and they keep failing.

My solution is to use an infrared transmitter, which will send a beam of invisible light toward the gear that spins on the motor assembly. The reflected light will be measured by a detector. The "gear" that spins has a notch in it, that moves the limit switches (which keep failing). I'm going to capitalize on this notch. Here's how it works. When the notch passes in front of the beam, it will reduce the amplitude of the light reaching the detector. I will use a comparator chip to activate either a relay, or a transistor switch when a preset threshold is crossed. This will then switch off the motor when it has reached either the upper, or lower limits. Easy money! (I guess if you have a EE degree). I will "pot" the transmitter/detector pair (potting is a substance that you can place electronic parts in and it hardens). I can then drill two holes in it, making this the same size exactly as the factory limit switches.
Whatdayathink??
 
I

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Discussion Starter #5
Sounds like a great Idea - to bad we can't figgure out what kills the switches. Im forced to assume that they are just getting oxidized, how much amperage traverses the switch? does it run the motor directly or does it control a relay? Obviously optical is a generally more reliable and accurate way to go but wouldn't it be easier just to find a better switch instead of having to mount a P.C. somewhere?
 

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joe,
whatever man!!! as long as you can pull it off...where do I ship my wing too and to whom do I write the check??? but this will still work like b4 right? that will turn the active aero on at 45mph and will turn it off below that right???? So, do it my friend and let us all know how it goes!!!!
 
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Discussion Starter #7
when my avtive area went bad i took it apart and saw that there are two switches what went up and down as what happened was that my gear skiped a tooth or two and both switches were open put the gear back the way the wear marks showed and everything worked my active areo has busted two times and that was the case every time
 

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For what it's worth, I shut off the Active Aero when the temperature drops below 50 degrees. Cold air is tough on moving parts. I have to check the owners manual to see if there is anything about Active Aero in cold weather.

Joe, your idea using light instead of the microswitches is great! Please let us know if you get it working, maybe you can put together a part list and instructions?

Brian
 
J

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Discussion Starter #9
Aquiring the parts now. Checked into different components. I will be going tonight to get them. I will be checking the current flow through the switches, and try to determine the mode of failure. Right now, I suspect transient voltages causing arcing across the switch contacts which eventually make them fail. I'm not sure about why it the failure is higher during cold weather. I even went so far as to seal the unit with silicone, and the switches with silicone, so I doubt it is oxidation of the contacts. I'll keep everyone posted on how it is coming on building this. Due to the tight space, I doubt you can put in a switch that will handle much more current flow due to size constraints. I think that solid state is the way to go, also eliminating the mechanical aspects and another mode of failure. I believe there may be quite a bit of current flow through these switches. I'll post my findings, so hang tight.

Joe
 
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