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someone who did manual air susp controls...


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I saw a post where someone rigged up manual controls for the solenoids for their air suspension...

 

I tried to search for it but alas, could not find it.

 

Does anyone remember who it was, or could point me to that thread, or...well...has done it and can talk about it?

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Yeah...saw your reply, and this is what I was thinking...

 

There are 5 solenoids/valves. One to release air into the "system" from the air tank, and one for each strut.

 

I was thinking about setting up a set of switches in the dash. One "master" button that would open the air tank, then 4 others, one for each strut.

 

All the relays have a +12v constant to them, it's the computer that activates the ground which then activates the solenoid...or at least, that is how I understand it.

 

So all I'd need to do is disconnect the height sensor connectors for each strut at the strut, then rig up my own switchable ground lead and I should be able to open the solenoids whenever I want to add air.

 

Hmmm...but what if I wanted to lower it? I'd need to hook up another switch to control the air discharge valve. But I wouldn't want to "ruin" that switch...'cause hopefully if I leave everything else alone the air compressor should automatically charge the air tank like everything else was "normal".

 

I could try to spoof the height sensors...but that seems a touch overly complex...and this system seems to be able to do pretty much the same thing.

 

Make sense?

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I dont know if it was my post or not, but I've done it recently.

Bought the hardware at Napa, its just a air shock line kit. Comes with the Schrader valve, you need 2 kits tho. Unless you can find/make a tee with a schrader on it.

You need to cut the air lines between the compressor and the solenoids, the 2 lines for the front shocks on one valve and the same for the rears. It can all be done at the left shock tower. Now you need to pull the big black flat connector loose so you can get to it. There are 4 wires that control the solenoids on each shock.

Drivers side front is black-green

Pass side front is yellow-green

Drivers side rear is yellow-blue

Pass side rear is green-white.

These are all on one side of the connector and easy to see.

What you need to do is wire these to a switch to grnd, this will open them to fill the shocks.

I wired the fronts together and the rears together, that way I filled the fronts together equally, the same for the rears.

But after all the work and money I spent doing this, they still leaked! The whole system was shot, even the body of the solenoids were leaking. I replaced o-rings and went thru everything but still had problems.

So today I finished installing the rear coilovers on it.

The fronts I did last week.

No more problems :cool:

If your system is in good condition this is an option, but it really doesnt fix it.

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Turbone, I'm thinking of doing something similar, but maybe keeping it a bit more simple.

 

If I go to the ECU controlling the air suspension, I could just take manual control of the grounds leading to all the solenoids myself. Rig up a switch for each one...solenoid ground -> switch -> ground. Flipping that switch would activate the solenoid myself. I'd want to control A) the air charge (tank to system) B) struts solenoids (to fill each strut individually) and C) air discharge.

 

By opening air charge and FR strut solenoid that strut would fill and raise. By opening FR strut solenoid and air discharge the strut would empty and lower.

 

I'd prefer to not have the flashing "error" on the dash...and hopefully disconnecting all the height sensor plugs would prevent that. And by only inturrpting those lines the rest of the system (ie the air compressor filling the air tank, etc) should remain functioning as normal.

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You will have to disconnect the computer then because it will try and over ride the inputs that you are giving it. Then you have more problems because then you have nothing telling the compressor to start and fill the tank. The solenoids are one way btw. When you open the air goes in and out. I think your making it more complicated by trying to manually adjust them individualy. Does the system work correctly now? And why would you want to do this?

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From what I understand from Subaru the compressor will fill the tank when the computer sees low pressure in the tank, or when there is a demand on the system for air...so that should be automatic. You can activate it simply by grounding the pressure switch or compressor relay.

 

One of the diagnostic tests you can do is to ground a strut solenoid and ground the air charge solenoid. That will fill the strut with air, and the computer will be perfectly happy to do so. The switches I am planning on installing would allow me to do that whenever I wanted.

 

I'd just be taking over for the computer in a couple areas, but leaving it to take care of the rest.

 

The computer isn't that bright...and I bet I can trick it into thinking it is working. It's like using an S-AFC..it inturupts the sensor signal going into the ECU which "tricks" the ECU into seeing a different sensor signal than it really is. Hell, with the wiring diagram I could even force it to believe that the height sensors are all reading "normal" regardless of ride height.

 

I must admit this is getting pretty complex...but there are two big reasons why I'd like to give this a shot. One, it is cheaper than buying a new front strut :D All I'd need is wire (which I have a ton of already) and some 12V switches (which are around a dollar and change each) and time. Two, it would be fun to do...a cool lil project!

 

My biggest concern is that the air suspension computer will throw error codes on the dash when none of the height switches are connected.

 

I'm pretty sure this will work...and work well.

Ya know...thinking it all 100% through now it actually won't be that complex at all. All the wires I need to fiddle with are at the ECU, so it's just a matter of running it all to where I want.

 

Of course...I say all this now from my computer...and when I try to do this, I'll completely destroy the air suspension and end up with coilvers :P

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someone mentioned that a bad height sensor on an XT6 air suspension will prevent the compressor from turning on. i can't verify that as i've never had that problem or tried anything with it.

 

i would be interested in having full control as well, but leaving the stock suspension computer intact most of the time. i'd like that function for driving off road and in the snow. if you get anywhere with this, let me know and take pictures or something. that would be awesome. i'll do the same if i get around to it, but it won't be anytime soon.

 

gary

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hmmmm if someone can do this, I'm very interested in learning how. I know where there's an XT6 which might have the air suspension still in it and since I'm also planning on doing the 5-lug, this is EXACTLY what I want to do. Iwas thinking about it last night..."Hmm I wonder if anyone on the board has done this yet....":D

 

here's a thought though...get a sensor that will click power on going to the compressor when the air pressure gets too low. Like a minitruck setup, plug it in and leave it so it recharges the tank itself.;)

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hmmmm if someone can do this, I'm very interested in learning how. I know where there's an XT6 which might have the air suspension still in it and since I'm also planning on doing the 5-lug, this is EXACTLY what I want to do. Iwas thinking about it last night..."Hmm I wonder if anyone on the board has done this yet....":D

 

here's a thought though...get a sensor that will click power on going to the compressor when the air pressure gets too low. Like a minitruck setup, plug it in and leave it so it recharges the tank itself.;)

One crazy thing I was thinking about doing was using a car stereo graphic equalizer to control the height on each corner...so I'd have sliders to adjust ride height :D But that would be pretty damn complex to do.

 

I'm going to try this "manual" solution first. In fact, I'll be testing out my ideas tomorrow and will let you folks know either late Friday or early Saturday.

 

And the car should automatically do that compressor recharge. The system "wants" to fill the struts off the air tank, not the compressor. The compressor only kicks on when there is detected low pressure in the tank. The stock computer pretty much already does that...sadly my method will be defeating the automatic filling of the struts, but the automatic filling of the air tank should still work...

 

...unless I'm not quite sure what you are getting at :P

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This was one of my former brainstorms that turned into a drizzle.

 

I was going to wire each monetary button for each strut, using a DPDT switch for

the master (one throw = inflate, other throw = deflate) w/ a center off position.

 

BTW The deflate ("discharge") solenoid is inside the compressor housing.

.

I was also going to tap into the height switches and have an indicator lamp above

and below each button.

Note: there are four reed switches in each strut, wired in a kind of parallel configuration.

But one can be used for "high" and one for "low"

 

I do believe disconnecting sensors and solenoids will cause the pooter to freak.

I was going to wire resistors of similar value to the components they replaced

and hope the ECU didn't get it's panties in a bunch.

 

I to was going to do this all at the AS brain.

 

Tank filling can be accomplished as you describe,

the cut out switch is a differential type. (10 atm - off, 8.5 atm - on)

The desiccant in the lines to tank fitting is there to prevent moisture

and icing of the lines/solenoids in sub freezing climates.

 

Good luck, appears to be a piece of cake.

Sold my rump roast (Air Suspended Suspension) car before I did this.

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i forgot to mention...on the XT6 there is actually a way to wire a momentary switch into only 2 wires under the drivers seat (where the computer is located). if you wire this switch with two particular wires you can throw the switch and it will raise the struts to the *high* level. if you throw the switch again it will lower the car to the *standard* level. i know 3 people that have done this on the XT6 and gotten it to work, i tried last winter and it was not working on mine for some reason. there appear to be very minor discrepencies in wiring on certain vehicles (at least on mine)???? not sure, but mine wouldn't work but others didn't seem to have a problem. i tried 3 different computers and still no luck. unfortunately i don't know the two wires off the top of my head and it's confusing to explain it over email. best to look at the FSM wiring diagram, the computer is already wired for height control (the canadian models have selctable height control, the pod on the left has the height control button that the US models do not). just splice a switch into the appropriate two wires and yo'ure done. i'd like to look into it one more time and try to get mine to work. the US and Canadian models are identical...the US models have the same computer and circuitry, they just don't have the button in the control pod. this would be by far the easiest way to accomplish any height control. wouldn't have full control, but would give you a high and low. i'm really pissed i couldn't get mine to work. i hope someone here can get it to work and show pictures or document the exact wires.

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Oh MAN! I am soooooo close to getting it all figured out! I was able to isolate several of the circuts I needed...and could manually raise the FR strut with a simple ground setup.

 

I'm still struggling a bit here though, a couple lil minor issues.

 

I REALLY and desperately need the ECU pin outs diagram for the air suspension computer. I was able to "trial and error" test and find several of the ones I wanted, but am still missing a bunch of 'em. Doh! Dang Haynes manual doesn't have 'em...just engine ECU.

 

And yes...it is still rather annoyingly complicated, but not inansely though. Woot!

 

Soon...VERY soon.

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Well, I was able to accomplish something!

 

Phase One: Find Air Suspension ECU and figure out which wire is what...that was a bit of a pain but after seeing the wiring diagram turns out I had identified nearly all the correct wires. I cut two wires...the "Air Charge" wire (which opens the solenoid that runs air into the system from the tank) and the "Front Passenger" strut solenoid (that was the one that wasn't working...bad height sensor). I can take those two wires and ground 'em...and low and behold, the strut rises! Woo hoo! The computer still controls the rest of the struts...but cannot open the "Air Charge" valve on it's own...which is a lil scary right now.

 

But no error messages, everything still works as it should.

 

Now it's just a matter of cutting the rest of the solenoids, rigging up switches...and off I go!

 

I'm still a lil worried about lowering...I know which wire will open the "Air Discharge" solenoid...well, we shall see...

 

Awesome...simply awesome!

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