problem with my Sanden OBA

[austinaubinoe]

ok so I just finished plumbing my Onboard air setup. I like to think im pretty good mechanically, but I always seem to screw up wiring!

let me just describe my wiring first, hopefully this is the issue.

Viair 110-150 pressure switch mounted on tank (the one with the relay in it-40Amp)

4 wires come off of it:

------Ground, screwed to floor with a self tapper

------battery, 10awg to 40a fuse to positive terminal

------compressor, wired it to the only wire I could find coming off my 2000 sanden

-------Switch, wired to positive side of SPST toggle (neg side grounded to sheet metal)

Seems pretty simple to me, ANy ideas? Here is a dumb question.. The bigger rubber line closest to the passenger fender is the intake and the smaller line is the high pressure RIGHT? Another.... should I be worried about accidentally flipping the on switch with the engine is off?

Ill post some pictures of my new setup when I get a chance.

 

[WB9YZU]

So... What exactly is the problem. You never stated it. No clutch action?

You don't need a relay, just a pressure switch. The Sanden's clutch does not take much power.

Mine is wired thus:

(+)---< Toggle Switch >---< Pressure Switch >---< Compressor Clutch >(-)

Yes, if I flip the switch on when the engine is not running, the Clutch still engages when the air bleeds off. You can put it on the accy line so that it will only activate if the accy switch and the toggle is on.

 

[austinaubinoe]

well I am getting zero response when I flip the switch. I wired in a LED indicator light, and thats isnt lighting up either.

This is the pressure switch I bought: http://www.viaircorp.com/OffRoad/Parts/pswitchrelay.html


I found a wiring diagram on Viar's site, all looks the same, except the have a "keyed power source" going to the positive of the switch as well as the wire from the relay/pressure switch.

I was under the impression that the main battery power line power the compressor and relay. Guess I should wire the switch to the ignition as well.

 

[GREASYHANDS]

switch the power to the other side of the led and see if it works

 

[WB9YZU]

Old thread! I hope you figured it out


If you didn't...
The relay you bought has a constant 12V power for one side of the relay.
The other powered lead is labeled "Keyed Power" and goes to your accy switch.
The Ground lead is your relay ground return.
The "To Compressor" is your switched power for your compressor, and is where you would hook the clutch wire for the Sanden.

When there is no pressure on the switch, it activates the relay using the switched power source. The other power source is then switched by the relay to activate the clutch.

If you want the LED to activate when your compressor does, put the LED between the lead to the compressor, though a 4.7K ohm resistor to ground (Delete resistor if you are using an all in one "LED" from an auto supply shop).