Thoughts on constructing a Lowering switch

DieselDan

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Hey everyone,
I know a lot of people want to do this and since all the Ray Switch info is gone and locked away somewhere, I figured we might all be able to brainstorm here.

I had a few ideas and I know the principals that make the air suspension tick. I need to look at some wiring diagrams and try to come up with something.

First thought I had was cutting the harness at the air suspension module and installing a male/female aftermarket connector in series to the air suspension module so that the "lowering device" could be removed/installed, and not affect the stock operation of the air suspension, and there would be no ugly spliced and cut wires rattling around under the dash.

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Anyway, I know that the height sensors work on resistance values and I know that you need to just trick the module into thinking the car is sitting higher/lower than it actually is. I suppose this could be done with 2 potentiometers, 1 for the front and 1 for the rear. I know that the Ray switch was a little fancier because if I recall correctly it used push buttons and a LED display. I would probably guess 2 numbered rheostat assemblies wired in series with the height sensor circuits could do the trick. I need to look at a wiring diagram, or just ohm a height sensor through its entire range of motion to get my resistance range, something like the below picture...

!CEQs)D!!mk~$(KGrHqMOKjcE0w3y3rrDBNRYCUIM,w~~_12.jpg


Anyway, I am brainstorming this idea. I think all the M8 owners with air suspension are missing out on being able to have control over ride height. I think this should be a easy (don't quote me), however the principal sounds simple enough. Please keep input positive, and knowledgable. Don't trash the thread up basically, please!

Thank You
 
i thought the rays switch just slammed it for shows and the ASHAM8 was the adjustable one.
 
Thinking about it, you may need a separate control for left front/right front/and rear. If you were to tie both front sensors together, you would lose left side/right side leveling. I know my initial idea is a little crude, but you gotta start somewhere.

Something else I was also thinking about was an auxilairy air tank mounted in trunk. You could T the reservoir into the air lines at the rear air bags and it will charge the whole system with air via the air drier assembly. The auxilary air tank would be regulated down to the operating pressure of the stock compressor. I suppose it could also be pumped up a little to increase response time when the vehicle raises, but it might not really make a difference, due to the lines having a pretty small inside diameter. The auxilairy air tank would only be necessary if you would like to slam the car frequently, keeping the work off of the compressor. If the tank ran low, you would probably just hear the compressor run longer, and know that you need to fill the tank back up.

Again, thinking out loud...
 
i thought the rays switch just slammed it for shows and the ASHAM8 was the adjustable one.

I am not sure about that... Are we allowed to take pictures of the Ray switch and the ASHAM8? I know we arent supposed to take pictures of the Spider valve, didn't know if the same applied. Pictures would help because some of the work has already been done.

I am not looking to make these switches for the masses, however I think it would be great if a simple design could be made so that members could build their own. Just a single point of information on this topic would really help.
 
Hmm... There would have to be a fill solenoid on the auxilairy tank to fill the system, otherwise the tank would be emptied when the vent solenoid was opened. You could probably wire a fill solenoid to open when the compressor is turned on...
 
More thinking outloud. I am trying to keep the operation as simple as possible, because that is what usually works best.

A couple ways this could be done. You could assume manual operation of the system, kind of like the link I posted above. It just allows you to open/close solenoids and run the compressor. Using a relay, it looks like you can keep it from turning on the check air suspension message. I think this is the principal for the Ray Switch.

The other way to control it could be to allow the system to operate normally, just modify the inputs from the height sensors. Either way works I suppose, it just matters more what you are into. I think that this setup would allow you to allow the factory module to still raise/lower based on speed, and load level. You could also drive the car in a lowered height all the time without perpetually having a check air suspension message.

A way I was considering, but not sure of is having a control panel that would act as the air suspension shut off switch and manually fill/vent the bags. This would be more for parking the car lowered, or raise it up as tall as possible if maybe you had to get under the car for something. You could then flip the switch and recycle the ignition and normal operation would take over.
 
I don't know if this helps but at nominal ride height, the sensors will display 2.5v at the air ride controller. You would have to come up with a circuit that would output to the controller what the sensors are seeing in normal mode. When in lowered or raised mode, the circuit would have to output the controller what it would normally see (virtual sensors) and then be able to control the solenoids and/or the compressor relay which is what the asham8 does. Doing it like the .org article mentions means you are going to have to individually adjust each air spring without any indication of how much drop of lift you have at each corner. I think it would be much easier if you got someone on here to take very detailed notes and photos of their asham8 and then take it to an electronics buddy and have them build you one. Or you could just buy one http://members.chello.hu/breda.belarobert/asham8/
 
It looks like controlling the height sensor inputs to the AS module on pins 7, 8, and 9 on the black connector, this would be the easiest, less nonesense approach to this. You could control height without having to recycle the igntion, and you would have full function of the stock air suspension...
 
Wow... totally thought you could not get an asham8 or ray switch anymore... This is interesting.
 
Anyway, I know that the height sensors work on resistance values and I know that you need to just trick the module into thinking the car is sitting higher/lower than it actually is. I suppose this could be done with 2 potentiometers, 1 for the front and 1 for the rear. I know that the Ray switch was a little fancier because if I recall correctly it used push buttons and a LED display. I would probably guess 2 numbered rheostat assemblies wired in series with the height sensor circuits could do the trick. I need to look at a wiring diagram, or just ohm a height sensor through its entire range of motion to get my resistance range, something like the below picture...
the rays switch only had a switch, a couple relays, and a timer relay
i thought the rays switch just slammed it for shows and the ASHAM8 was the adjustable one.
yup
Thinking about it, you may need a separate control for left front/right front/and rear. If you were to tie both front sensors together, you would lose left side/right side leveling. I know my initial idea is a little crude, but you gotta start somewhere.

Something else I was also thinking about was an auxilairy air tank mounted in trunk. You could T the reservoir into the air lines at the rear air bags and it will charge the whole system with air via the air drier assembly. The auxilary air tank would be regulated down to the operating pressure of the stock compressor. I suppose it could also be pumped up a little to increase response time when the vehicle raises, but it might not really make a difference, due to the lines having a pretty small inside diameter. The auxilairy air tank would only be necessary if you would like to slam the car frequently, keeping the work off of the compressor. If the tank ran low, you would probably just hear the compressor run longer, and know that you need to fill the tank back up.

Again, thinking out loud...
the rays switch still leaves the stock system completely operational till you slam it

i spoke with ray and eddie about adding a tank to the existing system, and unless you completely start over it wont work, the comp wont know the tank psi to maintain it and the stock computer wouldn't be able to keep up with the fast lift, so it would go up then vent then go up again. im experiencing this a little bit using 2 compressors and a bigger vent. if you want it to lift quick add a second compressor it cut my lift from a full drop from 90 sec (yes just one cycle) to 45, its still not lighting fast but the lines are small so that would be the next restriction
I am not sure about that... Are we allowed to take pictures of the Ray switch and the ASHAM8? I know we arent supposed to take pictures of the Spider valve, didn't know if the same applied. Pictures would help because some of the work has already been done.

I am not looking to make these switches for the masses, however I think it would be great if a simple design could be made so that members could build their own. Just a single point of information on this topic would really help.
the spider valve is something you could look at and possibly make, a rays switch looks like a ball of wife with a switch on the end of it
Wow... totally thought you could not get an asham8 or ray switch anymore... This is interesting.
96hotrodlincoln took over with the switches when ray passed. being the new daddy he is a little tough to get a hold of
 
It's not the highest on my list of priorities, but I just want a switch that will go between ~1" lower than stock, and stock (well, slightly sensor lowered.)
 
That was some good reading ford nut, thank you. An idea that has been rolling around in my head is bypassing the sensors, maybe a 3 position toggle switch, one position is uninterrupted signal from the height sensors........

Hold on, on my phone, gonna type this on the computer.
 
I emailed him a few weeks ago, he said it would take a couple weeks to build but he still did them.
Hummm, I wonder if my work spam filter bounced his e mail.

Are you going to get one?


That was some good reading ford nut, thank you. An idea that has been rolling around in my head is bypassing the sensors, maybe a 3 position toggle switch, one position is uninterrupted signal from the height sensors........

Hold on, on my phone, gonna type this on the computer.

No problem, I have been kicking this around too.

Just not sure who is left with air ride that would like to mod it.
 
As I was saying, this was what was running through my head, but I gotta think it out a little more, because now I am not sure it will work...
Anyway, a 3 pole 3 position toggle switch that maybe in position 1, would allow uninterrupted flow from the height sensors to the AS module. I had a previous thought for second position, but now I can't think of it, i'll come back to it. Third position would use 3 rheostat knobs to immitate each sensor. I still need to learn what the voltages are, but from briefly looking, I believe it is a 5 volt reference to the sensor and the variable resistance of the sensor drops the voltage to whatever the computer sees it as height. Say .5-1.0volts slammed, to maybe 4.5-5.0volts sky high. You could use the dials to immitate that voltage drop... However, this is something I was thinking wouldn't work... The AS computer has to see movement in the sensors while it is either filling or venting to not throw a check suspension message...

Considering the idea of using the same setup I mentioned previously about the toggle switch, but maybe use the dials to either add or subtract voltage from the signal... Possibly use resistors to drop the voltage, or regulated voltage to add either 1 - 2volts. The computer would still see movement of the sensors, but it would be altered by +/- a few volts and the computer would not know, it would operate normally.

I assume this is how the ASHAM8 functions, just in a prettier backage with the digital display and the pushbuttons...
 
Maybe, power the board/module that is finally constructed with a 5 volt reference itself... Use resistors to function almost like a blower motor resistor works. Use a 5 position rheostat dial...
I am just thinking outloud again, but here goes. These are hypothetical voltages, since at the moment, I don't know what they are. However I think it is right, and it would work backwards between front to back, since they operate opposite in their resistances.

Positions:
1.)Resistance drop 5v to 0.5v-1.5v - Lowest/Highest position
2.)Resistance drop 5v to 1.5v-2.5v
3.)Resistance drop 5v to 2.5v-3.5v
4.)Resistance drop 5v to 3.5v-4.5v - Lowest/Highest position
5.)Normal Operation Setting: No resistance at this position, this would allow proper operation at your permanent normal ride height, based on the stock positioning of your height sensors. Basically where your car rides normally now.

You would also not want to "slam" the suspension. Well, you could, but you want to atleast leave a few PSI in the bags to alleviate strain on the compressor. If you completely deflate the bags, you will have to wait longer for the car to rais, and more likely for the compressor to time out if you do slam it. I personally would probably stop the drop maybe 1cm from full drop, just to keep air in the bags, but that is just me, and just another thought...
 
The above voltages would then be output to the the computer via whichever height sensor you wanted to control. Assuming that 0v-5v is what the AS computer will see through the height sensor's full travel, 0v-slamed, 5v-4x4 mode. So say 3volts is the sweet spot in the travel of the sensor, it knows that 3volts is midway between the suspension travel, and proper ride height. If you added 2volts, it would see 5 volts and realize the car is sitting too high, even though it isnt. It would vent until the sensor value was 1v and your input voltage from the switch was 2v. That would be slammed, but the car thinks it is at its sweet spot, or normal ride height. Thinking this through, I may have to tweak my voltage chart above, but this is still getting planned out.
 

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