RAS (rear air suspension) switch question:

[DRC]

I have a question for you v8 folks with the RAS. I have a v6 limited and will be installing some air bags for towing and I am hoping I can use one of the v8 center console switches from the factory RAS with my aftermarket system to raise / lower the suspension. It would be nice to fill one of the blanks I now have in my center console with a functioning switch.

I looked over a number of parts diagrams and found several part numbers that may work but I am unsure as I don’t have a good picture of the switch(s). One appears to be a simple on / off switch but I can’t tell what the other switch does. Can one of you v8 guys / gals that have the RAS tell me what switches you have, their position in the console and what they do?

Also, from my reading it sounds like the newer 4runners just have auto leveling RAS. Does this mean you cannot manually raise / lower the suspension? I ask this because somewhere I read that some 4runners, maybe the 04/05, had a switch that allowed you to adjust the height manually. Can someone confirm if any of the models have an up / down type switch for raising / lowering the RAS?

Thanks much!

 

[ARK_SWAMP_RIDER]

I don't have a pic, and I'm going off memory cause I'm not around my 4runner at the moment, but I'll give this a shot. I have the seat heater dials on the far left and far right. In between there are three switches, DAC, rear height adjust (arrows up and down), and a button to turn off rear height adjust. The RAS has three positions: low, normal, and high. The rear height adjust switch you can raise or lower it to the preset spot. As soon as you hit a certain speed (~20 mph), it automatically kicks back to the normal position. It does have the auto level feature, that's the whole point of RAS and all of them should work the same regardless of year. The RAS off button simply turns off the auto level feature. If needed, I can get you a pic first thing tomorrow. I think that should answer your questions, but if there's something else just let me know.

 

[ARK_SWAMP_RIDER]

Here's a pic I that I already had, you can kinda see the switch layout. I will order them from passenger to drivers side. Seat heater, then ride height control off, then ride height adjust up/down, then DAC, then the other seat heater. Hope that helps.

 

[DRC]

Thank you ARK_SWAMP_RIDER.

...The RAS has three positions: low, normal, and high. The rear height adjust switch you can raise or lower it to the preset spot...

The height adjustment switch is the one I am interested in. Can you tell me if the switch has 2 buttons: up and down or does it have 3 buttons: low, normal and high?

Also how do the buttons work? For example, do you push and hold the up button, assuming you have an up button, and it raises the suspension from "low" to "normal" to “high”.

What I am after is a switch that works like a toggle to deliver 12v DC while I hold the button but open the circuit when I release the button. If it’s a on / off type button, e.g. you click “high” and it stays on “high” this will not work for me.

Thanks again :hatsoff:

 

[ARK_SWAMP_RIDER]

If in the low position, you tap the up arrow and it raises it to normal. You tap the up arrow again and it goes to high. You do not have to press and hold. The opposite happened in high, press once to go to normal, press twice (you must wait until it's lowered to normal state before the second press).The switch is only a two way, up/down.

 

[Koz]

If in the low position, you tap the up arrow and it raises it to normal. You tap the up arrow again and it goes to high. You do not have to press and hold. The opposite happened in high, press once to go to normal, press twice (you must wait until it's lowered to normal state before the second press).The switch is only a two way, up/down.

If I'm not mistaken you can go from low to high by hitting the switch twice. You will see the display on dash blink high until it reaches the high setting, then the display light stays lit.


Koz

 

[ARK_SWAMP_RIDER]

OK, I'll have to confim that in a little while.

 

[jetboy1975]

From low position it will stop at level with one push of the button. Need to push it again to raise to high position. Can't remember if you have to wait until it gets to level before pushing again to go high though or if 2 pushes at once will do it. Don't have T4R with me but can check later or I'm sure someone can chime in.

 

[ARK_SWAMP_RIDER]

OK, I have confirmed that if it is on low, two quick presses will put it on high. I was thinking you had to wait till it got to normal, but that is incorrect.

 

[DRC]

Thanks everyone. This is exactly what I wanted to know. It sounds like I will be able to use this switch to control my air compressor to fill / drain the air bags. Now I just need to figure out where to mount the pressure gauge.

Here is the information for anyone else who may be interested:

Toyota part number: 8924935070
Description: Suspension control #2 - Limited 2005 - 2009
Price: $50.00 (or so)

See parts diagram, figure #12
http://www.utoyot8.com/images/82069091/146744689.png

Thanks all! :hatsoff:

 

[ARK_SWAMP_RIDER]

I've considered ditching the OEM rear air and going to coils with bags, just didn't know how to do that but also keep the switch functioning. If you get this worked out, please let me know. The OEM RAS really has me limited in lift options, so I'm trying to explore other options. My thing is I'd also like to utilize the factory compressor, which I don't know if that's possible or not either.

 

[DRC]

I've considered ditching the OEM rear air and going to coils with bags, just didn't know how to do that but also keep the switch functioning. If you get this worked out, please let me know.

Once I get the switch ordered and have a chance to try it out I will post back and let everyone know the status. It maybe a week or two by the time I get the switch and some space cleaned up in my garage.

The OEM RAS really has me limited in lift options, so I'm trying to explore other options. My thing is I'd also like to utilize the factory compressor, which I don't know if that's possible or not either.

In theory it should be possible. In looking at the wiring diagram it looks like the Height Control Compressor (H13) will turn on when given a 12v current to fill the bags and the Height Control Valve (H17) would open a relief valve when given 12v current to release pressure.

However, from the diagram, it looks like the system has independent control of the left and right side via 2 relief valves. So you could raise / lower the left independent from the right. This might be a bit tricky to get working with a single up / down switch. They do many after market systems that work like this but I believe you have 2 switches, one to raise / lower the left and one to raise / lower the right. In the OEM 4runner system they are controlled electronically by the Suspension Control ECU and the pressure sensors.

Assuming you wanted to control the back as one single unit, e.g. both left and right go up / down together, I don’t see why you could not use the OEM parts. Based on the wire diagram, if you installed after market bags and connected them in series to the compressor and relief value you could then wire the up side of the Height Control Switch (H12) directly to H13 and the down side directly to H17, contact 1 or 3. You would need to choose either the left valve, contact 1, or the right valve, contact 3, since you would be running the bags in series. Of course you would need to “permanently” turn the OEM system off. But you could do this by simply disconnecting the Height Control Switch (H119).

In theory and on paper it should work.:wink2:

 

[DRC]

Sorry after posting I realized the wire diagram is hard to see and I forgot to mention this is from a 2006 4runner, just incase things have changed.

I have a zip file that has the full set of wire diagrams for the 4runner as PDF files, about 4mb in size. I’ll try and find a way to post them to the forum but in the mean time if anyone wants them just let me know and I will send them to ya.

 

[ARK_SWAMP_RIDER]

^^Soungs great in writing, but in all honesty that's WAY over my head and capabilities. It will be nice to know that it's possible. I'm discussing the suspension with a guy I know, he *might* be able to make me a custom lift for the rear that will work with the OEM rear air system with no modification. Thanks for the info, I'll definitely save that for later reference.

 

[bandit60]

Sorry to dig up an old thread.

Anyone ever get the stock compressor wired up to control aftermarket air bags inside coils?

I'm looking to install airlift bags inside my swapped in coils. Would be nice to have them hooked up to the air compressor left over from the stock air suspension.