Aux Out for XFI

[Jeff Rand]

Do all four aux outs trigger by going to ground. I have my shifter set up thinking that aux 1 out would send out 12 volts when activated. The funny thing is that it worked so I was wondering if there was a switch that could switch the aux from ground to
12v (it was a few years ago that I did the install and I don't remember if that was an option). Bottom line is the CO2 shifter has stopped working. The CO2 and solenoid have checked out OK. What a lousy feeling when you expect the shifter to shift and the engine hits the rev limiter.
Thanks,
Jeff

 

[karolko]

Yes all the Aux outputs switch to ground. About the only thing that recieves a 12v signal on the xfi that most people would use is the PA Enable (b19)

Hope this helps. I would think that if you backfed the aux outputs with 12v, you could possibly hurt the ECM, unless htey have diodes in there.

Adrian

 

[TurboDave]

Jeff, I think the aux outputs on most aftermarket ecm's are active grounds. I could be wrong but I believe it would be problematic having aux outputs provide a 12v signal. Simply because a 12v output would require some hefty drivers because of the endless variety of loads that could be hooked up. Electronically speaking and for ease of "packaging" it's much easier to have the outputs go to active ground.

You could use the aux output to provide a ground signal to a relay, and have that relay provide the 12v signal you need.

It's how I use the aux fuel pump output on my Translator Pro. It's also an active ground. I have a relay with 12v one side of the relay's coil, and the aux provides a ground (when triggered) to the other side, energizing the relay. This provides power to my "second" staged fuel pump at a specified boost level.

 

[Jeff Rand]

I don't think I backfed 12v. At first glance I might have backfed ground but if that happened the shifter would never worked. I need to tear into it to see if and where I am picking up 12v.
Thanks for the information.

 

[Jeff Rand]

I just took another look at the shifter solenoid and one side is grounded and the other side went to aux 1. I know it has worked in the past but it had a mind of its own (occassionally it would not work). I thought it might have been the solenoid or the CO2 regulator. Now I wonder how it worked at all.
Jeff

 

[HighPSI]

The aux outputs have always been switched ground. You have to run it to a relay if you are going to use it on the shifter solenoid. If you try and use it to directly switch the ground on the shifter solenoid, it could damage the XFI. You may be able to wire it directly to a Dedenbear (or any other type of control box), if you are using one.

 

[Jeff Rand]

The aux outputs have always been switched ground. You have to run it to a relay if you are going to use it on the shifter solenoid. If you try and use it to directly switch the ground on the shifter solenoid, it could damage the XFI. You may be able to wire it directly to a Dedenbear (or any other type of control box), if you are using one.

Thanks Cal, I will rewire it today. What type of damage would you expect to see if it was wired direct?

 

[HighPSI]

It might damage that circuit on the board. The rest of the XFI should be fine. If you wire it correctly and it works then you didn't damage it

 

[TurboDave]

must be an echo in here.

 

[Turbo Loyd]

I called FAST technical support about wiring the torque converter lock up and they suggested not wiring the XFI to ground output to the ground side of the TCC solenoid, but to use a relay as an interface. Their concern was a solenoid may have significantly lower resistance thus draw heavier current than the output to ground driver can withstand, as Cal mentioned above.