Deciphering almost any Automotive Combination Switch Assembly

I was recently working on a project that involved using a combination switch assembly used “normally” in the cars for Indicating Directions, Wipers, Headlights and Horns! For those who work on such projects which involves using things which are made for something else to do things that they usually dont do..this might be the post that can get u going and you can Decipher the full console/part in about 10-15 minutes.

Usually the generic way is to check each and every connection using a DMM as a continuity tester and figure out which switch closes which connection..which is very lengthy and often makes one impatient.

Here are a few tips/steps/way outs/notes/whatever:

  1. Open the console(only the outer covering) to see where the wires land up. Never ever open a switch assembly because it might contain some springs or mechanical arrangement that might be difficult to re-assemble.

Rear Assembly “Almost Exploded”

Front Exploded View

2. In many of these Assemblies the switches for a common purpose are base colored the same while to distinguish between them line colors are given. Like in the photo below the green wires are for Indicators wherein the all green wire is Common, the Green-Red               ( Syntax: Base Color-Line Color) is the Left indicator and Green-Yellow is the right indicator. Once you find wires of common base colors ..probe one without any line color to ones with a line color but same base color. and do some mechanical movements..a beep will show the contact made..then carefully document it in a diary/notebook.

Wire Harness Connector

3.When you have still some connections left to decipher ..Follow the following algo:

  • Initiate a mechanical switch and analyse the movement..because it is obvious that somewhere in the world in your hands a contact is being made..it might be that some copper strips be making contact when a plastic bar presses the strip..or a metallic piece moving on a PCB pad.
  • Once you figure where the action takes place..probe the point and There you get the missing links.
  • Now if there are some more wires left..lets follow the principal of exclusion and work backwards..trace the wires back to the point of contact and see what sort of mechanical action produces that kind of a reaction.

PCB Pads and the copper strip for Wiper control and the Green-Red Wire of the Indicator System

Copper Strips and the black contactor that makes and breaks!

Hope you like the post and manage to decipher a few assemblies. Keep me posted on how this helped.

Happy Tinkering!

Arduino ControlWare v.1.0 Beta

I had a bit of an experience developing GUI`s and Data Visualization in Processing.Processing is very cool to work with and the designs are highly scale-able. There are tons and tons of separate examples and libraries available for processing especially the Serial Library which eases the task.

During this week , i tried to make myself a GUI using Visual C#. It was a really great experience.Although you can make buttons in processing too..but its a lot easier in Visual C# Express.However, it seems not many DIY`ers use C# and its used mainly by hardcore coders and developers..but still i managed to find some cool references via MSDN and a demo(of his work) by my friend to put together a simple and easy way to talk to Arduino on a windows machine!

You can monitor Analog Inputs , control digital pins and connect to the COM Port of your choice.Since i am still building upon it.So i am leaving a gist of how the GUI/program currently looks.

You will see that the Digital Pin 13 is missing. Actually i have used it to indicate an Active Serial Session.This makes it a lot easier while debugging.

ControlCom from Indian Tinker on Vimeo.

Edit: 02 Oct`12 : Thank You Guys for appreciating my work!I gave the same to few of my folks at my college for beta testing. Here is the link to the final executable on Windows Only!


The Arduino Code To be uploaded is :                                                      Source

Some of FAQ`s are:

  1. There is no Digital13 on this as it is meant to signify an active Serial Connection.i.e whether the computer is communicating with Arduino or not.
  2. You have to find out the correct COM Port from Device Manager and enter that with Caps On
  3. This is a VegBurgerWare ( coz i dont drink beer).So if i find u using it.You owe me a burger 😛
  4. Its not Cross Compatible..works best on Windows Only