Yet Another AUX Switches Thread!

[Rstamp99]

Please be gentle; I'm new, but I promise I've already looked for the answer.

Adding the AUX buttons to my 2016 RAM 2500 CC 6.7L.

The truck didn't have the aux button panel, but I got it with the correct top buttons already (TC, ExhBrk, Rear PA, Front PA) and, of course, AUX1-5 on the bottom row.

My question is, does anyone know exactly what the module does?

Exactly what connection is made internally when aux 1 (or any other aux #) is pushed?

I am unable to retrieve any information from the pins that the harness connects to on the back of the panel for the aux button pins.

I cannot tell that anything is connected pin to pin when those buttons are pushed.

I've already toned/ohmed every pin to every other pin and get nothing, no matter whether the button is pushed, pushed and held, or pushed and released.

There is no continuity across any two pins, regardless, leaving me baffled as to exactly how this thing can operate.

I already cut into the harness on the appropriate wires and added my own harness to extend those wires under the hood and wire them into a relay block for controlling lights/compressor/ AC inverter, etc.

Still, when I couldn't get ground continuity or 12V power at the ends, I started tracing it back to find a problem.

And finally, I'm at the switch panel itself, trying to determine what, if anything, these switches actually connect.

Hopefully, someone has already wrestled with this beast and has an answer.

The picture is the back of the aux switch panel I'm working with.

TIA!
Jim

 0 Comment(s)

[AK Bob]

Please be gentle; I'm new, but I promise I've already looked for the answer.

Adding the AUX buttons to my 2016 RAM 2500 CC 6.7L.

The truck didn't have the aux button panel, but I got it with the correct top buttons already (TC, ExhBrk, Rear PA, Front PA) and, of course, AUX1-5 on the bottom row.

My question is, does anyone know exactly what the module does?

Exactly what connection is made internally when aux 1 (or any other aux #) is pushed?

I am unable to retrieve any information from the pins that the harness connects to on the back of the panel for the aux button pins.

I cannot tell that anything is connected pin to pin when those buttons are pushed.

I've already toned/ohmed every pin to every other pin and get nothing, no matter whether the button is pushed, pushed and held, or pushed and released.

There is no continuity across any two pins, regardless, leaving me baffled as to exactly how this thing can operate.

I already cut into the harness on the appropriate wires and added my own harness to extend those wires under the hood and wire them into a relay block for controlling lights/compressor/ AC inverter, etc.

Still, when I couldn't get ground continuity or 12V power at the ends, I started tracing it back to find a problem.

And finally, I'm at the switch panel itself, trying to determine what, if anything, these switches actually connect.

Hopefully, someone has already wrestled with this beast and has an answer.

The picture is the back of the aux switch panel I'm working with.

TIA!
Jim

Unfortunately, I don’t have AUX switches on my truck and no experience with them.

Here is a video that has a good explanation and information on resources for them.

 0 Comment(s)

[Rstamp99]

Figured it out.

The aux switches do not connect any two (or more) poles together like a traditional switch.

They are simply the output wires from the Printed Circuit Board behind them, which in turn is connected to the BCM of the truck. Until I had the auxiliary switches added to my truck's computer (AlphaOBD and OBDLynkMX+ -- BCM -- Car Configuration Change -- [added snow plow, LIN Custom program features: auxiliary switches, PTO, and custom]).Set.Menu 1: Auxiliary Switches Present--switches 1-4] screenshots attached) The BCM or (whatever computer controls the aux panel) would not provide ANY output on those aux switch pins.

After adding the three options in AlphaOBD, the [COMMERCIAL] option appeared in the EVIC, and I was able to configure the aux switches to be either latching or momentary, as well as ignition on to be active or always active (battery).

I was then able to control the negative/ground side of five different circuits, which will feed a 6-channel relay block and add-ons.

This actually makes a lot of sense that the buttons don't function without involvement from a computer; otherwise, they wouldn't be configurable from latching to momentary, and from ignition-fed 12V or battery-fed 12V.

However, I had previously read threads where people installed the aux panels without adding the codes to the BCM, and the buttons still worked.

However, at least with my truck, that was not the case.

I hope this helps someone avoid chasing their tail for four days spread out over three months, like I did.

Screenshot_20251101-000033.jpg

Screenshot_20251031-235719.jpg

Screenshot_20251031-224823.jpg

 0 Comment(s)

[Blackgoat]

Yup

Can bus takes signals not take circuits of 12 volts.

 0 Comment(s)