So long story short i'm working on a project and i have a set of switches that has 19 buttons and only 6 wires. I need to find which wires are related to which buttons and the resistance for each button. what would be the best way to accomplish this?
Show us a drawing of the connections.
I understand neither the question nor the diagram; also wondering where the Arduino would fit in, but that might be because I don't understand.
Might just be me, but I think more explanation is required.
Hi,
Is the button assembly built by you, or is it a commercially available assembly?
Can you post a picture of it please?
Tom... 
Make sure that all pins are disconnected (infinite resistance?) if no button is pressed.
Then press one button and find out the pins with the resistance assigned to that button.
Repeat for all buttons.
Most probably there is a common pin for all buttons, which should be connected to Arduino Gnd, and the other pins going to ADC inputs.
For elvon_blunden the arduino would be at the input/output to read the signals coming from the buttons, I need to know the resistance for each button and which wire it feeds through.
For Tom George the button assembly is the factory steering wheel buttons for a 2017 Dodge Ram 1500, the can bus system is making everything harder for me. It’s not letting me post a picture right now and I’m heading to work, I’ll try and have one posted when I get home.
Hi,
Can you post a picture of the assembly please?
Do the wires come from a control unit built into the assembly?
What makes you think each button will have a different resistance?
Can you tell us your electronics, programming, arduino, hardware experience?
Tom...
TomGeorge:
Hi,
Can you post a picture of the assembly please?
Do the wires come from a control unit built into the assembly?What makes you think each button will have a different resistance?
Can you tell us your electronics, programming, arduino, hardware experience?
Tom...
The numbers are the numbers of buttons at each position
The system is originally part of a can bus in a 2017 dodge ram 1500, and from what I've read the system reads the button pushes by the difference in resistance for each button. I am trying to use these buttons in another vehicle by ultimately having an Arduino receive the resistances from these buttons and then relay the correct resistance signals out to the rest of the vehicle.
I have a decent background in electrical and some basic electronics, however I only have very basic experience with programming and computer circuits however but I am always up for a challenge and a chance to gain knowledge.
Hi,
Those two white modules have numbers on them, can you tell us what they are?
If they are canbus units then you will need to use a canbus interface to read them.
You need to get hold of a schematic of that area of the steering wheel to see what the various wires are designated.
The switch condition of OPEN or CLOSED will be read, so not just any resistance.
Tom...
The two modules are factory from Chrysler P# 68111384AB (left) and P# 56054449AA (right) but I haven't been able to get a wiring schematic for them so that's why i have been trying to find another way to determine which wires are on which switch circuit.
As far as the can bus shield, i am planning on using one but i dont know how to program it without telling is what it should be looking for.
I have found some information for an older version of this same system where the two 3 pole switches have set ohms as;
Seek up - 1.1k ohm
Mode - 500 ohm
Seek down - 2.9k ohm
Vol up - 5.3k ohm
Mute - 2.5 ohm
Vol down - 9.2k ohm
From here i just need to test if these are the same for this system or not and determine the same for the remainder of the switches.
Can this be done with some version of a basic ohm meter or would using a can bus shield be a better option?
DrDiettrich:
Make sure that all pins are disconnected (infinite resistance?) if no button is pressed.
Then press one button and find out the pins with the resistance assigned to that button.
Repeat for all buttons.Most probably there is a common pin for all buttons, which should be connected to Arduino Gnd, and the other pins going to ADC inputs.
What would be the best way to accomplish this without having to individually check each combination of wires for every switch.
Hi,
Have you unscrewed the modules and looked at what is underneath?
Tom...
Yes I looked at it, its a circuit board with prongs coming through the back cover for the wiring harness plug. I tried to trace the circuits but its a multi layer board and I lost them fairly quickly. I can post pictures if needed.
bcwilson21:
What would be the best way to accomplish this without having to individually check each combination of wires for every switch.
If you had started measuring already, instead of writing and waiting for answers, you had the result already :-]
My problem is that there are gonna be 285 different wire/switch combinations which will take forever to test. Just trying to find a quicker way to test them all
Then build an Arduino tester, that checks all combinations while you press a button